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61.
Hyeong Pil Kim Abd Rashid bin Mohd Yusoff Hyo Min Kim Hee Jae Lee Gi Jun Seo Jin Jang 《Nanoscale research letters》2014,9(1):150
We demonstrate that there is a new solution-processed electron transport layer, lithium-doped zinc oxide (LZO), with high-performance inverted organic photovoltaic device. The device exhibits a fill factor of 68.58%, an open circuit voltage of 0.86 V, a short-circuit current density of −9.35 cm/mA2 along with 5.49% power conversion efficiency. In addition, we studied the performance of blend ratio dependence on inverted organic photovoltaics. Our device also demonstrates a long stability shelf life over 4 weeks in air. 相似文献
62.
Uncrosslinked and chemically crosslinked ethylene‐vinyl acetate copolymers (EVAs) with 5–25 volume percentages of zeolite were prepared in a melt‐mixing process and then compression‐molded on a hot‐press machine according to standard test specifications. The mechanical properties measured by tensile test showed a reduction in tensile strength and elongation at break with increasing zeolite content. However, an increasing trend was observed for tensile modulus with addition of zeolite. Experimental results for ultimate stress were compared with those from Pukanszky equation. The experimental data showed a good fit to the Pukanszky model. The improvement in the interfacial interaction for crosslinked composites was also confirmed by this model. Morphological changes of EVA/zeolite composites were analyzed by scanning electron microscopy (SEM). The fractured surface of the composites indicated more complex morphology at higher zeolite loading. The influence of crosslinking induced by 2 wt% of dicumyl peroxide on the properties of EVA/zeolite composites was also investigated. The crosslinked composites showed better tensile properties than the uncrosslinked ones, a result which might be an indication of enhanced interaction between the EVA and zeolite. Density measurements, gel content determinations, and Fourier transform infrared analyses were also performed to evaluate the crosslink content of the composites. The changes in the properties of chemically crosslinked EVA/zeolite composites were observed. Meanwhile, SEM micrographs of the crosslinked EVA/zeolite composites showed better interfacial strength between zeolite and the EVA matrix as compared to that of the uncrosslinked composites. J. VINYL ADDIT. TECHNOL., 2012. © 2012 Society of Plastics Engineers 相似文献
63.
Khamirul Amin Matori Loy Chee Wah Mansor Hashim Ismayadi Ismail Mohd Hafiz Mohd Zaid 《International journal of molecular sciences》2012,13(12):16812-16821
We report on a recycling project in which α-Al2O3 was produced from aluminum cans because no such work has been reported in literature. Heated aluminum cans were mixed with 8.0 M of H2SO4 solution to form an Al2(SO4)3 solution. The Al2(SO4)3 salt was contained in a white semi-liquid solution with excess H2SO4; some unreacted aluminum pieces were also present. The solution was filtered and mixed with ethanol in a ratio of 2:3, to form a white solid of Al2(SO4)3·18H2O. The Al2(SO4)3·18H2O was calcined in an electrical furnace for 3 h at temperatures of 400–1400 °C. The heating and cooling rates were 10 °C/min. XRD was used to investigate the phase changes at different temperatures and XRF was used to determine the elemental composition in the alumina produced. A series of different alumina compositions, made by repeated dehydration and desulfonation of the Al2(SO4)3·18H2O, is reported. All transitional alumina phases produced at low temperatures were converted to α-Al2O3 at high temperatures. The X-ray diffraction results indicated that the α-Al2O3 phase was realized when the calcination temperature was at 1200 °C or higher. 相似文献
64.
A. A. Nuraini A. K. A. Mohd Ihsan M. J. M. Nor N. Jamaluddin 《Journal of Mechanical Science and Technology》2012,26(8):2405-2411
This paper presents the results of vibro-acoustic modeling and simulation using the finite element and the boundary element methods for the free piston engine structure. A model of the engine was constructed through the use of finite element software to perform a normal mode analysis of the engine structure. The objective was to determine the mode shapes and the natural frequency that contribute to engine structure vibration. Theoretical development of the engine balance motion and frequency response was also conducted. From the simulation and finite element analysis, the force response pattern of the engine vibration was determined and then compared with its natural frequency. The vibration data were used as the input data for noise analysis using the boundary element method. The integration of the finite element and the boundary element determined the noise-frequency data of the engine structure toward the occurrence of engine noise. The information can be used by designers to analyze engine specifications and structure, especially at the preliminary design stage. 相似文献
65.
Georgios Papadopoulos Hanna Kurniawati Ahmed Shafeeq Bin Mohd Shariff Liang Jie Wong Nicholas M. Patrikalakis 《野外机器人技术杂志》2014,31(2):225-244
Over the past 10 years, significant scientific effort has been dedicated to the problem of three‐dimensional (3‐D) surface reconstruction for structural systems. However, the critical area of marine structures remains insufficiently studied. The research presented here focuses on the problem of 3‐D surface reconstruction in the marine environment. This paper summarizes our hardware, software, and experimental contributions on surface reconstruction over the past few years (2008–2011). We propose the use of off‐the‐shelf sensors and a robotic platform to scan marine structures both above and below the waterline, and we develop a method and software system that uses the Ball Pivoting Algorithm (BPA) and the Poisson reconstruction algorithm to reconstruct 3‐D surface models of marine structures from the scanned data. We have tested our hardware and software systems extensively in Singapore waters, including operating in rough waters, where water currents are around 1–2 m/s. We present results on construction of various 3‐D models of marine structures, including slowly moving structures such as floating platforms, moving boats, and stationary jetties. Furthermore, the proposed surface reconstruction algorithm makes no use of any navigation sensor such as GPS, a Doppler velocity log, or an inertial navigation system. 相似文献
66.
Mohd Ikram Ramli Abu Bakar Sulong Norhamidi Muhamad Andanastuti Muchtar Mohd Yusuf Zakaria 《Ceramics International》2019,45(9):11648-11653
Composite biomaterials are in high demand in the medical field of today. The combination of bioactive wollastonite (WA) glass ceramic with the biocompatibility of alloy titanium (Ti6Al4V) could be a good candidate for implant applications. The rheological properties of Ti6Al4V/WA feedstock show a pseudoplastic behaviour with low activation energy. The feedstock was successfully injected as a green part with no defects. The green part was solvent debound for 6?h in heptane and thermal debound in an argon environment for 1?h. The brown part was successfully sintered at 1300?°C for 3?h with 5?°C/min heating and cooling rates. The average sintered density was 4.12?g/cm3; which is 97.5% from the theoretical density. The highest Young's modulus obtained was 18.10?GPa; which is in the range of human bone strength. EDX analysis shows that by increasing sintering temperature, the level of oxygen decreased. Cell viability test shown an absorbance increased with days increasing indicated that the cellular were proliferated on the composite Ti6Al4V/WA composite which also proved that the composite was non-toxic. This indicates that the Ti6Al4V/WA composite is suitable for bone implant applications. 相似文献
67.
Norazah Mohd Suki 《Electronic Commerce Research》2013,13(4):477-491
Shopping on the Internet enables consumers to search for information on products or services and make purchases through direct interaction with online retailers. This study investigates consumer shopping behaviour on the Internet based on four aspects, i.e. the Internet marketing environment, product characteristics, familiarity, and promotional offers. The impact of influencing factors was checked by questionnaire survey, which was then processed and evaluated. Two hundred randomly selected respondents (students and employees in a public higher learning institution in the Federal Territory of Labuan, Malaysia) participated in the survey. Multiple regression analysis was used as a statistical measure to determine the most influential relationship aspect among a series of independent variables of consumer shopping on the Internet. The results revealed that familiarity has a great influence on consumer shopping on the Internet, followed by promotional offers. The assimilation of these aspects, and the empirical examination of the factors that influence consumer shopping on the Internet, advanced understanding of these constructs and their link to dynamic technology deployment for shopping. The paper suggests managerially actionable implications, and future research directions. 相似文献
68.
Mohd-Shafie Muhammad Luqman Kadir Wan Mohd Nasir Wan Lichter Horst Khatibsyarbini Muhammad Isa Mohd Adham 《Software and Systems Modeling》2022,21(2):717-753
Software and Systems Modeling - Model-based test case generation (MB-TCG) and prioritization (MB-TCP) utilize models that represent the system under test (SUT) for test generation and... 相似文献
69.
Mohammad Asim Mohd T. Paridah M. Chandrasekar Rao M. Shahroze Mohammad Jawaid Mohammed Nasir Ramengmawii Siakeng 《Iranian Polymer Journal》2020,29(7):625-648
Natural fiber-based composites are applied in many structural engineered products from civil constructions to automobile manufacturing due to the properties such as low density, high aspect ratio, biodegradability and ease to work. During the past decades such composites have been thoroughly studied for their mechanical properties and failure behavior and their properties compared with those of synthetic fiber-based composites. Other properties, such as the thermal behavior of natural fibers and composites, have also been studied because they determine the performance of their products possible. It deals with the effect of temperature on adhesive curing, effect of high temperature and fire damage during fabrication. Further, the thermal properties have equal importance in structural applications such as temperature transfer from end to end, load capacity at specific temperature, material behavior and dimensional stability at high temperature. In this respect the isothermal and non-isothermal thermogravimatric analyses are discussed and the improtance of glass transition temperature is studied during prepapration of composites to ensure their ultimate properties. Although there are several works that have been done on thermal behavior, especially thermogravimetric analysis of natural fibers and their composites, there is no review article available specially focused on natural fiber-based composites, hybrid composites, and nanocomposites. The aim of this review was to focus on the advances in the comprehension of thermogravimetric behavior of natural fibers and compare the effect of natural fibers as reinforced materials in polymer composites. 相似文献
70.
Nurazni Amat Bahari Wan Nor Roslam Wan Isahak Mohd Shahbudin Masdar Zahira Yaakob 《国际能源研究杂志》2019,43(10):5128-5150
Hydrogen becomes one of the most clean energy sources. The major issues on hydrogen are lack of practical clean and high‐temperature processes and possible practical storage of clean hydrogen. An energy intensive of clean hydrogen storage via chemical and liquid fuel production route is the current demand. This article reviewed the most recent research for hydrogen (H2) production by using several methods, such as thermochemical process, thermal decomposition, biological approaches, electrolysis, and photocatalytic method. H2 storage types, including physical and chemical approaches, were also reviewed. The produced H2 was stored as valuable chemicals and fuels via CO2 hydrogenation reaction. Reactor designs are the illustrated number of design ranging from the fixed bed to the continuous stirred tank reactor. Catalyst type, catalytic system, and the related mechanism of CO2 hydrogenation reaction to form alcohol, alkanes, and carboxylic acid were also discussed in detail. 相似文献