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This research focuses on the effect of molar concentration of CuI thin film deposited by mist atomization technique. The result shows the CuI thin film properties strongly depends on its precursor concentration. Thickness between 0.35 x 10⁴ nm - 1.60 x 10⁴ nm was obtained as the concentration increases. The increment of thickness affects the electrical properties which is the resistivity and conductivity of CuI thin film. The resistivity of about 10¹ω cm to 10³ω cm was observed in those CuI thin films. For optical properties, the absorption coefficient and optical band gap of CuI was determined by using Tauc's plot. The high absorption coefficient of 10⁶ m^-1 is observed in those CuI thin films with bandgap between 2.84 to and 2.95eV obtained in this experiment.

The purpose of this study was to investigate the performance of a single-bridge ZnO nanorod as a photodetector.

The fabrication of the design sensor with ∼6-μm gap Schottky contacts and bridging of the ZnO nanorod were based on conventional photolithography and wet-etching technique. Prior to bridging, the ZnO nanorods were grown by the hydrothermal process. The 0.35 M seed solution was prepared by dissolving zinc acetate dihydrate in 2-methoxyethanol, and monoethanolamine, which acts as a stabilizer, was added drop-wise. Before starting the solution deposition, and oxide, titanium (Ti) and gold (Au) layer deposition, p-type (100) silicon substrate was cleaned with Radio Corporation of America (RCA1) and RCA2, followed by dipping in diluted hydrofluoric acid. The aged solution was dropped onto the surface of the Au microgap structure, using a spin coater at a spinning speed of 3,000 rpm for 45 seconds, and then dried at 300°C for 15 minutes, followed by annealing at 400°C for 1 hour. The hydrothermal growth was carried out in an aqueous solution of zinc nitrate hexahydrate (0.025 M) and hexamethyltetramine (0.025 M).

In this study, ZnO nanorods were grown on a SiO₂ substrate by the hydrothermal method. Microgap electrodes with ∼6-μm spacing were achieved by using the wet-etching process. After the growth process, an area-selective mask was utilized to reduce the number of rods between the nearby gap areas. The obtained single ZnO nanorod was tested for the UV-sensing application. The single ZnO nanorod photodetector exhibited a UV photoresponse, thereby indicating potential as a cost-effective UV detector. The response and recovery times of the fabricated device were 65 and 95 seconds, respectively. Structural analysis was captured using X-ray Diffraction (XRD), whereas surface morphology was determined using scanning electron microscopy.

This paper demonstrates the effect of UV photon on a single-bridge ZnO nanorod between microgap electrodes.

Two-dimensional (2D) problems are governed by unsteady anisotropic modified-Helmholtz equation of time–space dependent coefficients are considered. The problems are transformed into a boundary-only integral equation which can be solved numerically using a standard boundary element method (BEM). Some examples are solved to show the validity of the analysis and examine the accuracy of the numerical method.

The 2D problems which are governed by unsteady anisotropic modified-Helmholtz equation of time–space dependent coefficients are solved using a combined BEM and Laplace transform. The time–space dependent coefficient equation is reduced to a time-dependent coefficient equation using an analytical transformation. Then, the time-dependent coefficient equation is Laplace transformed to get a constant coefficient equation, which can be written as a boundary-only integral equation. By utilizing a BEM, this integral equation is solved to find numerical solutions to the problems in the frame of the Laplace transform. These solutions are then inversely transformed numerically to obtain solutions in the original time–space frame.

The main finding of this research is the derivation of a boundary-only integral equation for the solutions of initial-boundary value problems governed by a modified-Helmholtz equation of time–space dependent coefficients for anisotropic functionally graded materials with time-dependent properties.

The originality of the research lies on the time dependency of properties of the functionally graded material under consideration.

Since 2010, Swiss slaughterhouses have no longer accepted end-of-lay chickens, so egg producers have had to slaughter the animals on the farm and deliver them to biogas plants for gasification. However, the producers’ association, GalloCircle, has recently contracted a German slaughterhouse to process end-of-lay chickens into meat. As a consequence, an increasing number of these animals are now transported abroad. The purpose of this paper is to compare the two chains from a utilitarian perspective.

An interview with a central actor is analyzed by objective hermeneutics. In addition, a utilitarian comparison of the two chains is carried out.

The interview with a core stakeholder reveals that he considers this to be worse for both the animals and the farmers. The system change has been motivated by the (either merely perceived or actual) ethical preferences of consumers. The authors ethical evaluation of the system change shows, however, that highly controversial assumptions would need to be made in order to justify it. The authors doubt that the (alleged) consumer preferences are based on a proper ethical analysis of the two options.

The authors make a case for rationally reconsidering the choice of sending the chickens abroad.

The paper shows that utilitarian analysis is useful to consciously choose between different value chains.

Biotechnology is closely associated to microfluidics. During the last decade, designs of microfluidic devices such as geometries and scales have been modified and improved according to the applications for better performance. Numerous sensor technologies existing in the industry has potential use for clinical applications. Fabrication techniques of microfluidics initially rooted from the electromechanical systems (EMS) technology.

In this review, we emphasized on the most available manufacture approaches to fabricate microchannels, their applications and the properties which make them unique components in biological studies.

Major fundamental and technological advances demonstrate the enhancing of capabilities and improving the reliability of biosensors based on microfluidic. Several researchers have been reported verity of methods to fabricate different devices based on EMS technology due to the electroconductivity properties and their small size of them. Therefore, controlled fabrication method of MEMS plays an important role to design and fabricate a highly selective detection of medical devices in a variety of biological fluids. Stable, tight and reliable monitoring devices for biological components still remains a massive challenge and several studies focused on MEMS to fabricate simple and easy monitoring devices.

This paper is not submitted or under review in any other journal.

The purpose of this paper is to study the effect of hydrogen (H₂) gas on the graphene growth from fruit cover plastic waste (FCPW) and oil palm fibre (OPF), as a solid feedstock, towards the coefficient of friction (COF) properties.

Graphene film growth on copper (Cu) substrate was synthesised from FCPW and OPF, as a solid feedstock, using the chemical vapour deposition (CVD) method, at atmospheric pressure. The synthesised graphene was characterised using Raman spectroscopy, Scanning Electron Microscopy (SEM) and Electron Dispersed Spectroscopy (EDS). Surface hardness and roughness were measured using a nano-indenter and surface profilometer, respectively. Then, a dry sliding test was executed using a ball-on-disc tribometer at constant speed, sliding distance and load, with coated and uncoated copper sheet as the counter surface.

The presence of H₂ gas reduced the running-in time of the dry sliding test. However, there is no significant effect at the constant COF region, where the graphene growth from FCPW shows the lowest COF among other surfaces.

This paper is limited to graphene growth using the CVD method with selected parameters.

To the authors’ knowledge, this is the first paper on growing graphene from palm oil fiber via the CVD method and its subsequent analysis, based on friction coefficient properties.

This paper aims to examine the friction and wear performance of the graphene synthesized from fruit cover plastic waste and oil palm fiber (OPF).

The graphene was synthesized by using a chemical vapor deposition method, where a copper sheet was used as the substrate. The dry sliding test was performed by using a micro ball-on-disc tribometer at various sliding speeds and applied loads.

The results show that both as-grown graphenes decrease the coefficient of friction significantly. Likewise, the wear rate is also lower at higher sliding speed and applied load. For this study, OPF is proposed as the best solid carbon source for synthesizing the graphene.

The main contribution of this study is opening a new perspective on the potentials of producing graphene from solid waste materials and its effect on the tribological performance.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2019-0486

Zinc oxide (ZnO) is an emerging optoelectronic material due to its various functional behaviors. The purpose of this paper is to report on the fabrication and characterizations of ZnO microrods.

ZnO microrods were synthesized using sol‐gel immerse technique on oxidized silicon (Si) substrates. The oxidized Si substrates were immersed in ZnO aqueous solution for different times ranging from three to five hours. The surface morphologies of the ZnO microrods were examined using scanning electron microscope (SEM). In order to investigate the structural properties, the ZnO microrods were measured using an X‐ray diffractometer (XRD). The optical properties were measured using a photoluminescence (PL) spectrophotometer.

Characterization from SEM shows an enhanced growth of the ZnO rods with increasing immerse time. XRD characterizations demonstrate sharp and narrow diffraction peaks peculiar to ZnO, which implies that the rod is of high crystallinity. Based on the PL spectra, long immerse time results in the high peak in the UV region.

This paper concludes that the immerse time exerts an influence on the ZnO microrods. A longer immerse duration is preferred in the fabrication of the ZnO microrod, which is considered an emerging material for many advanced electronic and optoelectronic applications.