25 research outputs found
Reference-Plane Invariant Method for Measuring Electromagnetic Parameters of Materials
This paper presents a simple and effective wideband method for the
determination of material properties, such as the complex index of refraction
and the complex permittivity and permeability. The method is explicit
(non-iterative) and reference-plane invariant: it uses a certain combination of
scattering parameters in conjunction with group-velocity data. This technique
can be used to characterize both dielectric and magnetic materials. The
proposed method is verified experimentally within a frequency range between 2
to 18 GHz on polytetrafluoroethylene and polyvinylchloride samples. A
comprehensive error and stability analysis reveals that, similar to other
methods based on transmission/reflection measurement, the uncertainties are
larger at low frequencies and at the Fabry-Perot resonances.Comment: 12 pages, 21 figure
Nanostructured Materials under Ion and Microwave Radiation
This thesis discusses how ion radiation and microwaves interact with nanoscale-structured materials. In the case of ion radiation, the experiments show that ion processing, either with low-energy ions in reactive ion etching or with higher energy ions in focused ion beams, produces inelastic strain in polycrystalline thin metallic films. This results in the bending of thin strips of metallic films, which cannot be explained by elastic models. The concept of ion-induced plastic strain implies the insertion of adatoms into grain boundaries within the metal matrix. In ion etching processes, thin strips of metallic films with different widths were released from the substrate at different times. Therefore, the rate of atomic flow into grain boundaries is different for different strips. The larger curvatures in narrower strips are the result of a faster rate of adatom insertion into the grain boundaries. With a high-energy focused ion beam, plastic strain can be created locally, allowing the fabrication of non-trivial three-dimensional structures at nanometer scales. In the case of microwave radiation, the materials studied include cobalt nanoparticles and carbon nanotubes. The magnetic resonance and absorption in cobalt nanoparticles are observed in various magnetizing fields at frequencies between 0.5 and 18 GHz, by using a wideband method. The obtained experimental results show that the energy absorption is associated with the ferromagnetic resonance of cobalt nanoparticles. The results include measurements of blocking temperature and saturation magnetization with SQUID magnetometry. The absorption spectra are analyzed theoretically by combining Kittel's theory for uniaxial spherical particles, the Landau-Lifshitz-Gilbert equation and effective medium models. At zero magnetizing field, the observed resonance occurs at higher frequencies compared to the non-interacting particle model. The shift of resonance is suggested to be caused by the clustering of particles. Transmission electron microscopic images demonstrate that indeed particles aggregate in the forms of clusters, superlattices, and chains. The absorption properties of yarns of carbon nanotubes are also presented in the thesis
Ferromagnetic resonance in -Co magnetic composites
We investigate the electromagnetic properties of assemblies of nanoscale
-cobalt crystals with size range between 5 nm to 35 nm, embedded in a
polystyrene (PS) matrix, at microwave (1-12 GHz) frequencies. We investigate
the samples by transmission electron microscopy (TEM) imaging, demonstrating
that the particles aggregate and form chains and clusters. By using a broadband
coaxial-line method, we extract the magnetic permeability in the frequency
range from 1 to 12 GHz, and we study the shift of the ferromagnetic resonance
with respect to an externally applied magnetic field. We find that the
zero-magnetic field ferromagnetic resonant peak shifts towards higher
frequencies at finite magnetic fields, and the magnitude of complex
permeability is reduced. At fields larger than 2.5 kOe the resonant frequency
changes linearly with the applied magnetic field, demonstrating the transition
to a state in which the nanoparticles become dynamically decoupled. In this
regime, the particles inside clusters can be treated as non-interacting, and
the peak position can be predicted from Kittel's ferromagnetic resonance theory
for non-interacting uniaxial spherical particles combined with the
Landau-Lifshitz-Gilbert (LLG) equation. In contrast, at low magnetic fields
this magnetic order breaks down and the resonant frequency in zero magnetic
field reaches a saturation value reflecting the interparticle interactions as
resulting from aggregation. Our results show that the electromagnetic
properties of these composite materials can be tuned by external magnetic
fields and by changes in the aggregation structure.Comment: 14 pages, 13 figure
Development of a Multihole Atmospheric Plasma Jet for Growth Rate Enhancement of Broccoli Seeds
This work aims to develop a multihole atmospheric pressure plasma jet (APPJ) device to increase the plasma area and apply it to a continuous seed treatment system. Broccoli seed was used to study the effects of an atmospheric pressure plasma jet on seed germination and growth rate. An argon flow rate of 4.2 lpm, a plasma power of 412 W, and discharge frequency of 76 kHz were used for seed treatment. The contact angle decreased strongly with the increase in treatment time from 20 s to 80 s. The broccoli seedâs outer surface morphology seemed to have been slightly modified to a smoother surface by the plasma treatment during the treatment time of 80 s. However, the cross-sectional images resulted from Synchrotron radiation X-ray tomographic microscopy (SRXTM) confirmed no significant difference between seeds untreated and treated by plasma for 80 s. This result indicates that plasma does not affect the bulk characteristics of the seed but does provide delicate changes to the top thin layer on the seed surface. After seven days of cultivation, the seed treated by plasma for 30 s achieved the highest germination and yield
Computer-mediated discourse of L2 players in online gaming environments
ÂĐ 2014 Dr. Sarinya KhattiyaThe intent of this study is to examine computer-mediated discourse (CMD) of second language (L2) players in Massively Multiplayer Online Games (MMOGs). Three-dimensional MMOGs have gained massive global popularity; at the end of 2014 for example, it is predicted that there will be approximately 44 million paid gaming subscribers, more than double the number of those in 2009. Although some research has been conducted to investigate language use in such environments, discourse features of L2 players remains largely unexplored. Framed by CMD and language socialization theory, this two-part study first focuses on analysis of specific discourse features of players as they first begin to interact in the MMOG World of Warcraft over a period of six months. Analysis of the online interactions showed a range of significant results between native and non-native speakers in areas of language including typography, orthography and syntax. The results of this first stage of the study were then used to generate questions to further probe the reasons behind significant differences in overall discourse patterns. Using virtual ethnography techniques, including participant observation and semi-structured interviews, the second stage of the study was to investigate how language socialization processes occur in online gaming environments. Specifically, this second study addressed a deficit of research in CMD concerning L2 players, and seeks contribute to a better understanding of processes regarding online language socialization. Overall, the two studies in a single thesis make a contribution to the rapidly growing area of computer-mediated discourse analysis with implications for online language learning, language socialization and innovative research methods in applied linguistics
Port competitiveness of Laem Chabang Port, Thailand
Ports are very important for the national economy as well as social well-being since they are mostly involved with the import and export of goods. Moreover, world business increasingly focuses on activities which can add value to end customers. As a result, recent market activities become more aggressive in terms of port competition. For this reason, this study attempted to ascertain the port competitiveness of Laem Chabang Port (LCP), Thailand. At first, factors that are considered to be the most relevant to port competitiveness, are identified by means of reviewing the literatures, namely port location, services, hinterland connection, telecommunication and port charges. In addition, the current situation of maritime trade is analysed in different regions, which is Asia, Southeast Asia and Thailand. Moreover, the background of LCP is described, including its performance in the past decade.
This study aims to provide in-depth information on current practices and perceptions of the port, therefore, these factors are further carried out in an empirical section. In order to do so, interviews are conducted in this study. The sample group of this study are shippers, carriers, freight forwarders, which use LCP for import and export, Port Authority of Thailand, and local government organisation.
Based on each port competitiveness factor, LCP is carefully evaluated in order to indentify its competitive advantages. Moreover, LCP is critically compared to its main competitor, Singapore Port, the world top container port. Finally, a SWOT analysis is implemented so as to identify its strengths, weaknesses, opportunities and threats. By doing so, it helps LCP to manage development plans in the future in order to enhance its competitive advantages and become even more successful port in the global seaborne trade.Faculty of Social Science and Business / Plymouth Business School
CS17: Torsional vibration problem with recirculation gas blower due to variable frequency drive
Case StudiesThe centrifugal blower equipped with variable-frequency-drive (VFD) motor services in petrochemicalplant The unit was experienced many times of coupling failures after replacement new VFD,metallurgical study indicated torsional fatigue crack Supported by API 684, the VFD has beensuspected of the torsional excitation source Consequently, the torsional vibration was measured inthis study interacted with VFD characteristic The results showed operating with Direct Torque ControlMode, the oscillating torque increased dramatically due to closed-loop control interaction, to maintainthe speed of motor precisely by adjusting the internal torque reference Proper tune of speedcontroller parameters minimize oscillating torque less than five times Also, switching control mode toscalar mode, without closed-loop interaction, the torsional excitation was greatly reducedAs a result, it is decided to configure VFD operating in scalar mode control and compare the actualtorque was evaluated to the limited torque which coupling manufacturer recommende
āļāļļāļāļŠāļĄāļāļąāļāļīāļāļāļāļāļĩāđāļāļāļāļĨāļīāđāļĄāļāļĢāđāļāļāļāļāļĢāļĩāļāļāļĢāļļāļāļāļēāļāđāļāđāļēāļĨāļāļĒāđāļāļĨāđāļāļĩāļĒāļĄāļŠāļđāļāļāļŠāļĄāļāļēāļāđāļāļĨāđāļāļĩāļĒāļĄāļāļēāļĢāđāđāļāļāđProperties of Pervious Geopolymer Concrete Made from High-calcium Fly Ash Containing Calcium Carbide Residue
āļāļēāļāļ§āļīāļāļąāļĒāļāļĩāđāļĄāļĩāļāļļāļāļāļĢāļ°āļŠāļāļāđāđāļāļ·āđāļāļĻāļķāļāļĐāļēāļŠāļĄāļāļąāļāļīāļāļāļāļāļĩāđāļāļāļāļĨāļīāđāļĄāļāļĢāđāļāļāļāļāļĢāļĩāļāļāļĢāļļāļ āđāļāļĒāļĻāļķāļāļĐāļēāļāļēāļĢāđāļāđāļ§āļąāļŠāļāļļ 2 āļāļāļīāļ āđāļāđāđāļāđ āđāļāđāļēāļĨāļāļĒāđāļĨāļ°āļāļēāļāđāļāļĨāđāļāļĩāļĒāļĄāļāļēāļĢāđāđāļāļāđāđāļāđāļāļ§āļąāļŠāļāļļāļāļąāđāļāļāđāļāđāļĨāļ°āļ§āļąāļŠāļāļļāđāļĢāđāļāļāļēāļĢāļāđāļāļāļąāļ§āđāļāļāļēāļĢāļāļąāļāļāļēāļŠāļĄāļāļąāļāļīāļāļāļāļāļĩāđāļāļāļāļĨāļīāđāļĄāļāļĢāđāļāļāļāļāļĢāļĩāļāļāļĢāļļāļ āđāļāđāļāļēāļāđāļāļĨāđāļāļĩāļĒāļĄāļāļēāļĢāđāđāļāļāđāđāļāļāļāļĩāđāđāļāđāļāđāļēāļĨāļāļĒāļĢāđāļāļĒāļĨāļ° 0, 10, 20 āđāļĨāļ° 30 āđāļāļĒāļāđāļģāļŦāļāļąāļāļ§āļąāļŠāļāļļāļāļĢāļ°āļŠāļēāļ āđāļāļĒāđāļāđāļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāđāļāđāļāļĩāļĒāļĄāļāļīāļĨāļīāđāļāļāđāļĨāļ°āļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāđāļāđāļāļĩāļĒāļĄāđāļŪāļāļĢāļāļāđāļāļāđāđāļāđāļāļāļąāļ§āļāļģāļāļāļīāļāļīāļĢāļīāļĒāļēāđāļāļŠāđāļ§āļāļāļŠāļĄ āđāļĨāļ°āđāļāđāļāļąāļāļĢāļēāļŠāđāļ§āļāļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāđāļāđāļāļĩāļĒāļĄāļāļīāļĨāļīāđāļāļāļāđāļāļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāđāļāđāļāļĩāļĒāļĄāđāļŪāļāļĢāļāļāđāļāļāđāđāļāđāļēāļāļąāļ 2.0 āđāļĨāļ°āļāļąāļāļĢāļēāļŠāđāļ§āļāļāļāļāļĄāļ§āļĨāļĢāļ§āļĄāļŦāļĒāļēāļāļāđāļāļ§āļąāļŠāļāļļāļāļĢāļ°āļŠāļēāļāđāļāđāļēāļāļąāļ 8.0 āđāļĨāļ°āļāļąāļāļĢāļēāļŠāđāļ§āļāļāļāļāđāļŦāļĨāļ§āļāđāļāļ§āļąāļŠāļāļļāļāļĢāļ°āļŠāļēāļāđāļāđāļēāļāļąāļ 0.50 āļāļļāļāļāļąāļāļĢāļēāļŠāđāļ§āļāļāļŠāļĄ āđāļāļĒāļĻāļķāļāļĐāļēāļāļąāļāļāļąāļĒāļāļāļāļāļ§āļēāļĄāđāļāđāļĄāļāđāļāļāļāļāļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāđāļāđāļāļĩāļĒāļĄāđāļŪāļāļĢāļāļāđāļāļāđāđāļāđāļēāļāļąāļ 5, 10 āđāļĨāļ° 15 āđāļĄāļĨāļēāļĢāđ āđāļāļĒāļāļģāļāļēāļĢāļāļāļŠāļāļāļāļģāļĨāļąāļāļāļąāļ āļāļģāļĨāļąāļāļāļąāļ āļāļ§āļēāļĄāļŦāļāļēāđāļāđāļ āļāļąāļāļĢāļēāļŠāđāļ§āļāļāđāļāļāļ§āđāļēāļāđāļĨāļ°āļŠāļąāļĄāļāļĢāļ°āļŠāļīāļāļāļīāđāļāļēāļĢāļāļķāļĄāļāđāļēāļāļāļāļāļāđāļģāļāļāļāļāļĩāđāļāļāļāļĨāļīāđāļĄāļāļĢāđāļāļāļāļāļĢāļĩāļāļāļĢāļļāļ āļāļĨāļāļēāļĢāļāļāļŠāļāļāļāļāļ§āđāļē āļāļēāļĢāđāļāđāļāļēāļāđāļāļĨāđāļāļĩāļĒāļĄāļāļēāļĢāđāđāļāļāđāđāļāļāļāļĩāđāđāļāđāļēāļĨāļāļĒāļŠāļēāļĄāļēāļĢāļāļāļĢāļąāļāļāļĢāļļāļāļāļģāļĨāļąāļāļāļąāļāđāļĨāļ°āļāļģāļĨāļąāļāļāļąāļāļāļāļāļāļĩāđāļāļāļāļĨāļīāđāļĄāļāļĢāđāļāļāļāļāļĢāļĩāļāļāļĢāļļāļāđāļāđ āđāļāļĒāđāļāļāļēāļ°āļāļēāļĢāđāļāļāļāļĩāđāļāļēāļāđāļāļĨāđāļāļĩāļĒāļĄāļāļēāļĢāđāđāļāļāđāđāļāđāļāđāļēāļĨāļāļĒāļĢāđāļāļĒāļĨāļ° 10 āļāļŠāļĄāļāļąāļāļāļāļāļāļ§āļēāļĄāđāļāđāļĄāļāđāļāļāļāļāļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāđāļāđāļāļĩāļĒāļĄāđāļŪāļāļĢāļāļāđāļāļāđāđāļāđāļēāļāļąāļ 15 āđāļĄāļĨāļēāļĢāđ āļāļąāļāļĢāļēāļŠāđāļ§āļāļāļāļāđāļŦāļĨāļ§āļāđāļāļ§āļąāļŠāļāļļāļāļĢāļ°āļŠāļēāļāđāļāđāļēāļāļąāļ 0.50 āļŠāļēāļĄāļēāļĢāļāđāļŦāđāļāļģāļĨāļąāļāļāļąāļāļāļāļāļāļĩāđāļāļāļāļĨāļīāđāļĄāļāļĢāđāļāļāļāļāļĢāļĩāļāļāļĢāļļāļāļŠāļđāļāļŠāļļāļāļāļĩāđāļāļēāļĒāļļāļāļēāļĢāļāđāļĄ 28 āļ§āļąāļ āđāļāđāļēāļāļąāļ 79.41 āļāļīāđāļĨāļāļĢāļąāļĄāļāđāļāļāļēāļĢāļēāļāđāļāļāļāļīāđāļĄāļāļĢ āļāļāļāļāļēāļāļāļĩāđāļĒāļąāļāļāļāļ§āđāļēāļāđāļēāļāļ§āļēāļĄāļāļĢāļļāļāļāļĩāđāļāļēāļĒāļļāļāļēāļĢāļāđāļĄ 28 āļ§āļąāļ āļāļĒāļđāđāļĢāļ°āļŦāļ§āđāļēāļ 30.80â32.65% āđāļĨāļ°āļāđāļēāļŠāļąāļĄāļāļĢāļ°āļŠāļīāļāļāļīāđāļāļēāļĢāļāļķāļĄāļāđāļēāļāļāđāļģāļāļĩāđāļāļēāļĒāļļāļāļēāļĢāļāđāļĄ 28 āļ§āļąāļ āļĄāļĩāļāđāļēāļāļĒāļđāđāļĢāļ°āļŦāļ§āđāļēāļ 2.17â3.16 āđāļāļāļāļīāđāļĄāļāļĢ/āļ§āļīāļāļēāļāļĩThis research aims to study the properties of Pervious Geopolymer Concrete (PGC) by using Fly Ash (FA) and Calcium Carbide Residue (CCR) as a precursor and a promoter, respectively to develop the properties of PGC. The CCR was used to replace FA at the dosages of 0%, 10%, 20%, and 30% by weight of a binder. Sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) solutions were used as the liquid portion in the mixtures. The Na2SiO3-to-NaOH ratio of 2.0, coarse aggregate-to-binder ratio of 8.0, and alkali liquid/binder (L/B) ratio of 0.50 were used in all mixes. The different ratio of NaOH concentrations was at 5, 10, and 15 molar to test on the compressive strength, flexural strength, density, total void ratio, and water permeability coefficient of the PGCs. The test results found that the use of FA with CCR could enhance the compressive and flexural strengths of PGCs. A mixture of 10%CCR and 15M of concentrated NaOH mixed with 0.50 of L/B ratio gave the highest of 28-curing day compressive strength of PCGs, which was 79.41 ksc. Moreover, the void ratio and permeability coefficient at 28-curing days varied between 30.80â32.65% and 2.17â3.16 cm/s, respectively
āļāļļāļāļŠāļĄāļāļąāļāļīāđāļāļīāļāļāļĨāļāļāļāđāļāđāļēāļĨāļāļĒāđāļāļĨāđāļāļĩāļĒāļĄāļŠāļđāļāļāļĩāđāļāļāļāļĨāļīāđāļĄāļāļĢāđāļāļŠāļĄāļāļēāđāļāļāļīāļĨāļīāļāļēāļāļĩāđāļĄāļĩāļāļāļēāļāđāļāļāļāđāļēāļāļāļąāļMechanical Properties of High-calcium Fly Ash Geopolymer with Nano-SiO2 Particle Sizes
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Effect of Portland Cement Content on Compressive Strength and Elastic Modulus of High-Calcium Fly Ash Geopolymer Mortar Containing Various Type of Alkali Solution
āļāļāļāļ§āļēāļĄāļāļĩāđāđāļāđāļāļāļēāļĢāļĻāļķāļāļĐāļēāļāļĨāļāļĢāļ°āļāļāļāļāļāļāļāļīāļāļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāļāđāļēāļāļāđāļāļāļģāļĨāļąāļāļāļąāļ āđāļĨāļ°āļĄāļāļāļļāļĨāļąāļŠāļĒāļ·āļāļŦāļĒāļļāđāļāļāļāļāđāļāđāļēāļĨāļāļĒāđāļāļĨāđāļāļĩāļĒāļĄāļŠāļđāļāļāļĩāđāļāļāļāļĨāļīāđāļĄāļāļĢāđāļĄāļāļĢāđāļāļēāļĢāđāļāļŠāļĄāļāļđāļāļāļĩāđāļĄāļāļāđāļāļāļĢāđāļāđāļĨāļāļāđ āđāļāđāļēāļĨāļāļĒāđāļāļĨāđāļāļĩāļĒāļĄāļŠāļđāļāļāļđāļāđāļāļāļāļĩāđāļāđāļ§āļĒāļāļđāļāļāļĩāđāļĄāļāļāđāļāļāļĢāđāļāđāļĨāļāļāđāļĢāđāļāļĒāļĨāļ° 0, 5, 10, 15 āđāļĨāļ° 20 āđāļāļĒāļāđāļģāļŦāļāļąāļāļāļāļāļ§āļąāļŠāļāļļāļāļĢāļ°āļŠāļēāļ āļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāļāđāļēāļ 3 āļāļĢāļ°āđāļ āļ āļāļĢāļ°āļāļāļāļāđāļ§āļĒ āļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāđāļāđāļāļĩāļĒāļĄāđāļŪāļāļĢāļāļāđāļāļāđāļāļĩāđāļāļ§āļēāļĄāđāļāđāļĄāļāđāļ 10 āđāļĄāļĨāļēāļĢāđ āđāļāļĩāļĒāļāļāļĒāđāļēāļāđāļāļĩāļĒāļ§ (NH) āļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāđāļāđāļāļĩāļĒāļĄāđāļŪāļāļĢāļāļāđāļāļāđāđāļĨāļ°āļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāđāļāđāļāļĩāļĒāļĄāļāļīāļĨāļīāđāļāļāļāļŠāļĄāļāļąāļ (NHWG) āđāļĨāļ°āļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāđāļāđāļāļĩāļĒāļĄāļāļīāļĨāļīāđāļāļāđāļāļĩāļĒāļāļāļĒāđāļēāļāđāļāļĩāļĒāļ§ (WG) āļāļđāļāđāļāđāđāļāđāļāļāļāļāđāļŦāļĨāļ§āđāļāļŠāđāļ§āļāļāļŠāļĄ āđāļāļĒāļāļģāļāļēāļĢāļāļāļŠāļāļāļāļģāļĨāļąāļāļāļąāļ āđāļĨāļ°āļĄāļāļāļļāļĨāļąāļŠāļĒāļ·āļāļŦāļĒāļļāđāļāļāļāļāđāļāđāļēāļĨāļāļĒāđāļāļĨāđāļāļĩāļĒāļĄāļŠāļđāļāļāļĩāđāļāļāļāļĨāļīāđāļĄāļāļĢāđāļĄāļāļĢāđāļāļēāļĢāđ āļāļĨāļāļēāļĢāļāļāļŠāļāļāļāļāļ§āđāļē āļāļēāļĢāđāļāđāļāļđāļāļāļĩāđāļĄāļāļāđāļāļāļĢāđāļāđāļĨāļāļāđāđāļāļāļāļĩāđāđāļāđāļēāļĨāļāļĒāđāļāļĨāđāļāļĩāļĒāļĄāļŠāļđāļāļŠāļēāļĄāļēāļĢāļāļāļĢāļąāļāļāļĢāļļāļāļāļģāļĨāļąāļāļāļąāļ āđāļĨāļ°āļĄāļāļāļļāļĨāļąāļŠāļĒāļ·āļāļŦāļĒāļļāđāļāļāļāļāđāļāđāļēāļĨāļāļĒāđāļāļĨāđāļāļĩāļĒāļĄāļŠāļđāļāļāļĩāđāļāļāļāļĨāļīāđāļĄāļāļĢāđāļĄāļāļĢāđāļāļēāļĢāđāđāļāđ āļāļķāđāļāļāļģāļĨāļąāļāļāļąāļāļāļāļāđāļāđāļēāļĨāļāļĒāđāļāļĨāđāļāļĩāļĒāļĄāļŠāļđāļāļāļĩāđāļāļāļāļĨāļīāđāļĄāļāļĢāđāļĄāļāļĢāđāļāļēāļĢāđāļāļķāđāļāļāļĒāļđāđāļāļąāļāļ§āļąāļŠāļāļļāļāļąāđāļāļāđāļāļāļĩāđāđāļāđ āđāļĨāļ°āļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāļāđāļēāļāļāļĩāđāđāļāđāđāļāļŠāđāļ§āļāļāļŠāļĄ āđāļāļĒāļāļēāļĢāđāļāđāļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāđāļāđāļāļĩāļĒāļĄāđāļŪāļāļĢāļāļāđāļāļāđ āđāļĨāļ°āļŠāļēāļĢāļĨāļ°āļĨāļēāļĒāđāļāđāļāļĩāļĒāļĄāļāļīāļĨāļīāđāļāļāļāļŠāļĄāļāļąāļ (NHWG) āļŠāļēāļĄāļēāļĢāļāđāļŦāđāļāļģāļĨāļąāļāļāļąāļāļŠāļđāļāļŠāļļāļāļāļāļāđāļāđāļēāļĨāļāļĒāđāļāļĨāđāļāļĩāļĒāļĄāļŠāļđāļāļāļĩāđāļāļāļāļĨāļīāđāļĄāļāļĢāđāļĄāļāļĢāđāļāļēāļĢāđāļāļŠāļĄāļāļđāļāļāļĩāđāļĄāļāļāđāļāļāļĢāđāļāđāļĨāļāļāđThis article aims to study the effect of alkaline solution types on compressive strength and elastic modulus of high-calcium fly ash (FA) geopolymer containing Portland cement (PC). FA was replaced by PC at the dosages of 0%, 5%, 10%, 15%, and 20% by weight of the binder. Three types of alkaline solutions viz., sodium hydroxide solution (NH), sodium silicate solution (WG), and NH plus WG solution (NHWG) were used as the liquid portion in the mixture. The compressive strength and elastic modulus of highcalcium FA geopolymer mortar were investigated. Test results indicated that the use of PC to replace FA could enhance the compressive strength and elastic modulus of high-calcium FA geopolymer mortar. The compressive strength of high-calcium FA geopolymer mortar depended on the types of source materials and alkali activators. The increase in PC content enhanced the compressive strength and elastic modulus of high-calcium FA geopolymer mortar. Finally, the use of NHWG showed the highest compressive strength of high-calcium FA geopolymer mortar containing PC