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The inherent uncertainty in hydro-geotechnical parameters presents a significant challenge for accurately predicting rainfall-triggered shallow landslides in mountainous regions. In this study, a novel probabilistic framework was developed and implemented in the “Py.GIS-FSLAM-FORM” software, designed to address the complexities associated with parameter uncertainty, correlation, and distribution. By combining the Fast Shallow Landslide Assessment Model (FSLAM) with the First-Order Reliability Method (FORM), we have enhanced the traditional probabilistic approach to create more accurate landslide susceptibility maps. This study emphasizes the uncertainly of geotechnical parameters and the critical influence of hydrological conditions on landslide susceptibility, especially focusing on the interaction between antecedent recharge (qa) and event rainfall (Pe). In our study area (Val d’Aran, Spain), the probabilistically based results revealed that areas of very high susceptibility are significantly affected by event rainfall, particularly on slopes of 30–40 degrees and aspects between 100 and 250 degrees. The variability in geotechnical parameters, especially the coefficient of variation (COV) in cohesion and friction angle, plays a crucial role in landslide susceptibility assessment, with increased COVs leading to greater landslide uncertainty. Additionally, cross-negative correlations and non-normal distributions of geotechnical parameters substantially influence the spatial distribution of landslides, notably when combining antecedent recharge with event rainfall. These results highlight the importance of incorporating parameter variability and hydrological conditions in susceptibility models to improve the precision of regional landslide forecasts. While the study was performed in Val d'Aran, its methodologies and conclusions are relevant to mountainous areas worldwide, offering insights for refining landslide prediction models and susceptibility assessments, contri, Peer Reviewed, Postprint (published version)

Microfluidic systems for biochemical reactions require efficient microfluidic actuation. However, current microfluidic devices are facing challenges in terms of self-powering and precise transport of microfluidics. This study demonstrates a novel approach to fabricating a self-powered and precise microfluidic manipulation system based on triboelectric nanogenerator (TENG) and electrowetting-on-dielectric (EWOD) technologies. The TENG provides high pulsed voltage and electrical wetting capabilities, enabling the manipulation system to drive microfluidic transport through electric field forces. The self-powered microfluidic device is systematically investigated by the effect of various parameters, including TENG power, TENG structures, EWOD/microfluidic device structures and surface hydrophobic properties. By optimizing the parameters, optimal performances are achieved in microfluidic motion, particularly in terms of precise two-dimensional movement. The movable volume range spans from 20 nl to 1.4 ml, representing one of the most notable achievements of TENG in the field so far. Additionally, the self-powered microfluidic system successfully synthesized multiple morphological ZnO nanoparticles, a rarely reported accomplishment. Finally, the novel self-powered system demonstrates the capability to detect chloride in disinfected water and COVID-19 antigen detection. This work proposes a novel TENG-EWOD microfluidic control technology that shows promise in various applications, including chemical processes, biological health testing and microdevice fabrication.

Triboelectric nanogenerators (TENGs) are considered one of the most effective methods for harvesting irregular and low-frequency raindrop energy. In this work, molybdenum selenide (MoSe2) nanosheets act as intermediate layers for improving droplet-based TENG performance. Consequently, without surface etching process, the short-circuit current (Isc) and open-circuit voltage (Voc) of the TENG can reach as high as 1.2 mA and 120 V, respectively. Furthermore, precise energy analysis based on an optimization model for input energy calculation is carried out, allowing conversion efficiency to be calculated under diverse conditions. Finally, an all-solid supercapacitor is fabricated for integration with the TENG. An intelligent wireless sensing system, powered by the integrated TENG and capacitor, is demonstrated for monitoring environmental information. This study provides new insights into intermediate-layer materials' selection and action mechanisms. It fills a gap in the research on a precise model of theoretical energy conversion efficiency calculation. The integrated devices and sensing applications will provide strategies for creating smart cities.

Infectious diseases are spreading rapidly with the flow of the world's population, and the prevention of epidemic diseases is particularly important for public and personal health. Therefore, there is an urgent need to develop a simple, efficient and non-toxic method to control the spread of bacteria and viruses. The newly developed triboelectric nanogenerator (TENG) can generate a high voltage, which inhibits bacterial reproduction. However, the output performance is the main factor limiting real-world applications of TENGs. Herein, we report a soft-contact fiber-structure TENG to avoid insufficient friction states and to improve the output, especially at a high rotation speed. Rabbit hair, carbon nanotubes, polyvinylidene difluoride film and paper all contain fiber structures that are used to guarantee soft contact between the friction layers and improve the contact state and abrasion problem. Compared with a direct-contact triboelectric nanogenerator, the outputs of this soft-contact fiber-structure TENG are improved by about 350%. Meanwhile, the open-circuit voltage can be enhanced to 3440 V, which solves the matching problems when driving high-voltage devices. A TENG-driven ultraviolet sterilization system is then developed. The bactericidal rate of this sterilization system can reach 91%, which significantly reduces the risk of disease spread. This work improves a forward-looking strategy to improve the output and service life of the TENG. It also expands the applications of self-powered TENG sterilization systems.

Wearable electronics with multifunction and convenience are entering a period of rapid development. However, the longer people wear electronic devices, the easier it is for bacteria to infect the skin. Sterilization of wearables has received little research, partly because mature high-voltage sterilization systems require energy sources, which will greatly restrict the large-scale applications of wearable devices. Therefore, a self-powered sterilization system with high comfort and safety is strongly appealing. To solve the above problem, we design a wearable, self-powered sterilization system with a biocompatible nano/ microporous fiber triboelectric nanogenerator (NMF-TENG) as the energy source and an interdigital electrode for better bactericidal performance. Ag nanowires (AgNWs) and carbon nanotube (CNT) are added to the indium tin oxide (ITO)-based interdigital electrode to improve the conductivity, bending performance, and local electric field strength. Due to the tip effect, the local electric field of the electrode can be improved as high as 1 MV m-1 , which can kill the bacteria. The system can achieve a long-term sterilization rate of up to 90%, which has great application potential in the sterilization direction of wearable electronic devices.

With the growing economy and technology, disease prevention and individual health are becoming more and more important. It is highly urgent to develop a non-toxic, self-powered, and safe high-voltage power source to prevent diseases spread by mosquitoes, especially in isolated or remote areas. Herein, we reported a high-performance rotary triboelectric nanogenerator (R-TENG) based on customized theoretical simulations and a ferroelectric nanocomposite intermediate layer. The customized theoretical simulations based on gradient electrode gaps were established to optimize gap angles and segment numbers of the electrodes, which could prevent air breakdown and enhance the R-TENG output energy by at least 1.5 times. Meanwhile, the electrical output performance of the TENG was further enhanced with a highly oriented BaTiO3 (BTO) nanoparticles intermediate layer by about 2.5 times. The open-circuit voltage of R-TENG reached more than 6 kV and could continuously light 3420 light-emitting devices (LEDs) or 4 serially connected 36 W household fluorescent lamps. Therefore, a self-powered high-voltage disease prevention system is developed based on the high-performance R-TENG to reduce the risk of disease transmission. This work provides a prospective strategy for the further development of TENGs and expands practical applications of self-powered and high-voltage systems.

Various heat-resistant alloys have been used in industry; however, the bridge between the bulk mechanical properties and the underlying micro- and nanoscopic local properties remains an issue. In the Special Issue on the topic of “Multiscale Modelling and Characterization of Mechanical Properties in Heat-Resistant Alloys”, both theoretical and experimental approaches were discussed to evaluate its mechanical properties from multiscale aspects. In the Special Issue, six original articles were published. T. Saito et al. [1] and T. Chen et al. [2] investigated creep behavior; T. Saito et al. [1] focused on the deformation mechanism of a single-crystal high-entropy superalloy at intermediate temperature from theoretical and experimental aspects. T. Chen et al. [2] developed a measurement method of strain-rate-dependent plasticity using a high-temperature instrumented indentation test and its computational simulations. E. Bonifaz and I. Watanabe [3] developed a multiscale simulation method for an arc-welded joint, in which the residual stress state after the welding process was estimated in consideration of the anisotropic microstructure. Y. Yamabe-Mitarai et al. [4] and H. Park et al. [5] investigated the mechanical properties of high-temperature wrought alloys; Y. Yamabe-Mitarai et al. [4] studied the correlation between solution treatment temperature, microstructure, and yield strength. H. Park et al. [5] developed an inverse analysis method of the stress–strain curve from a high-temperature compression test. H. Zhou et al. [6] studied the relationship between the microstructure and mechanical property in a powder metallurgy. The state-of-the-art technologies are condensed in the above-mentioned articles. We hope that they will be helpful for further research.

Various heat-resistant alloys have been used in industry; however, the bridge between the bulk mechanical properties and the underlying micro- and nanoscopic local properties remains an issue. In the Special Issue on the topic of “Multiscale Modelling and Characterization of Mechanical Properties in Heat-Resistant Alloys”, both theoretical and experimental approaches were discussed to evaluate its mechanical properties from multiscale aspects. In the Special Issue, six original articles were published. T. Saito et al. [1] and T. Chen et al. [2] investigated creep behavior; T. Saito et al. [1] focused on the deformation mechanism of a single-crystal high-entropy superalloy at intermediate temperature from theoretical and experimental aspects. T. Chen et al. [2] developed a measurement method of strain-rate-dependent plasticity using a high-temperature instrumented indentation test and its computational simulations. E. Bonifaz and I. Watanabe [3] developed a multiscale simulation method for an arc-welded joint, in which the residual stress state after the welding process was estimated in consideration of the anisotropic microstructure. Y. Yamabe-Mitarai et al. [4] and H. Park et al. [5] investigated the mechanical properties of high-temperature wrought alloys; Y. Yamabe-Mitarai et al. [4] studied the correlation between solution treatment temperature, microstructure, and yield strength. H. Park et al. [5] developed an inverse analysis method of the stress–strain curve from a high-temperature compression test. H. Zhou et al. [6] studied the relationship between the microstructure and mechanical property in a powder metallurgy. The state-of-the-art technologies are condensed in the above-mentioned articles. We hope that they will be helpful for further research.

Herein, we constructed urchin-like TiO2 hollow nanospheres (HNSs) by hydrothermal targeted etching, and used it as a substrate to load semi-metal 1T'-MoS2 nanosheets as effective nitrogen reduction reaction (NRR) electrocatalysts. 1T '-MoS2/TiO2 HNSs composites display outstanding NRR activity with the highest NH3 yield of 29.62 mu g h(-1) mg(cat)(.)(-1) at -0.75 V versus RHE. Besides, the highest FE of 24.9% is obtained at -0.65 V. The remarkable NRR performance is attributed to the high conductivity of 1T '-MoS2 and the urchin-like structure of TiO2 hollow nanospheres. DFT calculations display that the 1T'-MoS2 in 1T '-MoS2/TiO2 makes the activation and further reduction of {*}N-2 more thermodynamically favorable than pristine TiO2, contributing to better NRR catalytic activities. N-15 isotopic labeling experiment reveals that N in produced NH3 comes from N-2 of electrolyte.

The use of CSA cement in practice has been hindered by its unstable performance and short shelf-life caused by the prehydration of CSA clinker. In this study, the effect of ambient humidity on the prehydration rate and process of CSA clinker was investigated. The prehydration degree, ageing progress, and the dynamic change of mineral composition of CSA clinker exposed to five different relative humidities (ranging from 23% to 98%) for up to 180 days were studied. Experiments revealed that the ambient humidity of 60% RH can be considered a threshold value for storage of CSA clinker. Exposure of CSA clinker to RH higher than 60% will not only result in a significant decrease of hydraulic reactivity, but also in agglomeration of the clinker. Although the exposure of CSA clinker to RH lower than 60% has little effect on the hydraulic reactivity, the main hydration peak was found to be slightly delayed with the increase of RH., Accepted Author Manuscript, Materials and Environment

Herein, we constructed urchin-like TiO2 hollow nanospheres (HNSs) by hydrothermal targeted etching, and used it as a substrate to load semi-metal 1T'-MoS2 nanosheets as effective nitrogen reduction reaction (NRR) electrocatalysts. 1T '-MoS2/TiO2 HNSs composites display outstanding NRR activity with the highest NH3 yield of 29.62 mu g h(-1) mg(cat)(.)(-1) at -0.75 V versus RHE. Besides, the highest FE of 24.9% is obtained at -0.65 V. The remarkable NRR performance is attributed to the high conductivity of 1T '-MoS2 and the urchin-like structure of TiO2 hollow nanospheres. DFT calculations display that the 1T'-MoS2 in 1T '-MoS2/TiO2 makes the activation and further reduction of {*}N-2 more thermodynamically favorable than pristine TiO2, contributing to better NRR catalytic activities. N-15 isotopic labeling experiment reveals that N in produced NH3 comes from N-2 of electrolyte.

The growth kinetics play key roles in determining the chirality distribution of the grown single-walled carbon nanotubes (SWCNTs). However, the lack of comprehensive understandings on the SWCNT’s growth mechanism at the atomic scale greatly hinders SWCNT chirality-selective synthesis. Here, we establish a general model, where the dislocation theory is a specific case, to describe the etching agent–dependent growth kinetics of SWCNTs on solid catalyst particles. In particular, the growth kinetics of SWCNTs in the absence of etching agent is validated by both in situ environmental transmission electron microscopy and ex situ chemical vapor deposition growth of SWCNTs. On the basis of the new theory of SWCNT’s growth kinetics, we successfully explained the selective growth of (2n, n) SWCNTs. This study provides another degree of freedom for SWCNT controlled synthesis and opens a new strategy to achieve chirality-selective synthesis of (2n, n) SWCNTs using solid catalysts.

Creep and shrinkage are such properties that will occur in concrete when they are under load and exposed to surrounding. Since this property will cause deformation which may decrease the design strength of the concrete, it is necessary to do have more knowledge on this phenomenon. So, we will study the effect of creep on 7 and 14 days of cured time of specimens which sealed or unsealed will be considered, respectively. The specimens have shown how the concrete strains when they are under sustained load with time. Besides, the sealed specimens have shown how the basic creep is different from the total creep of concrete. Further, the specimens of loading at different ages have shown how the age at application of load influences creep. The result of the experiment has shown the relationship of strain under sustained load and time. Moreover, it is shown that creep is mainly related to the strength developed in the concrete.

The relationship between water permeability and different levels of the tested layers from the top surface to the bottom surface of the lightweight concrete specimens is determined in this study. It is beneficial to develop the design criteria for a durable lightweight concrete. The water permeability coefficient K of the samples was determined by water permeability test using GWT. It is found that the water permeability coefficient K of the three layers in each set of samples tends to decrease as the level of the tested from the top surface increase. Larger Rebound Number and higher density in the bottom layer and more coarse lightweight aggregates in top layer correlate with the result of the descending water permeability trend and also indicate the existence of floatation of lightweight aggregates. Therefore, concrete uniform is very important for lightweight concrete.

Elucidating the evolution of bimetallic catalyst for nucleating carbon nanotube has been challenging. In this work, acorn-like Pt-Fe2O3 nanoparticles are developed for the growth of single-walled carbon nanotubes (SWCNTs) by chemical vapor deposition. Using in situ environmental transmission electron microscopy, restructuring of the acorn-like Pt-Fe2O3 nanoparticles at reaction conditions is investigated. Upon heating to reaction temperature, ε-Fe2O3 is converted to β-Fe2O3, which can be subsequently reduced to metallic Fe once introducing CO. As Pt promotes the carburization of Fe, part of the metallic Fe reacts with active carbon atoms to form Fe2.5C instead of Fe3C, catalyzing the nucleation of carbon nanotubes. Nanobeam electron diffraction characterizations on SWCNTs grown under ambient pressure at 800 °C demonstrate that their chiral angle and diameter distributions are similar to those of SWCNTs grown on monometallic Fe. The results further indicate that the active components in both the catalysts, determining the chirality distribution of SWCNTs, are similar. In addition, Pt facilitates the reduction of Fe2O3, rendering SWCNT growth at a relatively low temperature of 700 °C. This work provides a profound understanding of the structural reconstruction in bimetallic catalyst, shedding more light on designing novel catalysts for the growth of SWCNTs.

Carbon nanotubes (CNTs) have excellent mechanical properties and can be used to reinforce cement-based materials. On the other hand, the reaction product of carbonation with hydroxides in hydrated cement paste can reduce the porosity of cement-based materials. In this study, a novel method to improve the strength of cement paste was developed through a synergy of carbon nanotubes decorated with carboxyl group and carbonation reactions. The experimental results showed that the carboxyl group (-COOH) of decorated carbon nanotubes and the surfactant can control the morphology of the calcium carbonate crystal of carbonation products in hydrated cement paste. The spindle-like calcium carbonate crystals showed great morphological differences from those observed in the conventional carbonation of cement paste. The spindle-like calcium carbonate crystals can serve as fiber-like reinforcements to reinforce the cement paste. By the synergy of the carbon nanotubes and carbonation reactions, the compressive and flexural strengths of cement paste were significantly improved and increased by 14% and 55%, respectively, when compared to those of plain cement paste.

Creep and shrinkage are such properties that will occur in concrete when they are under load and exposed to surrounding. Since this property will cause deformation which may decrease the design strength of the concrete, it is necessary to do have more knowledge on this phenomenon. So, we will study the effect of creep on 7 and 14 days of cured time of specimens which sealed or unsealed will be considered, respectively. The specimens have shown how the concrete strains when they are under sustained load with time. Besides, the sealed specimens have shown how the basic creep is different from the total creep of concrete. Further, the specimens of loading at different ages have shown how the age at application of load influences creep. The result of the experiment has shown the relationship of strain under sustained load and time. Moreover, it is shown that creep is mainly related to the strength developed in the concrete.

The relationship between water permeability and different levels of the tested layers from the top surface to the bottom surface of the lightweight concrete specimens is determined in this study. It is beneficial to develop the design criteria for a durable lightweight concrete. The water permeability coefficient K of the samples was determined by water permeability test using GWT. It is found that the water permeability coefficient K of the three layers in each set of samples tends to decrease as the level of the tested from the top surface increase. Larger Rebound Number and higher density in the bottom layer and more coarse lightweight aggregates in top layer correlate with the result of the descending water permeability trend and also indicate the existence of floatation of lightweight aggregates. Therefore, concrete uniform is very important for lightweight concrete.

Catalyst selection is very crucial for controlled growth of single-walled carbon nanotubes (SWNTs). Here we introduce a well-designed Fe-Ti-O solid solution for SWNT growth with a high preference to large chiral angles. The Fe-Ti-O catalyst was prepared by combining Ti layer deposition onto premade Fe nanoparticles with subsequent high-temperature air calcination, which favours the formation of a homogeneous Fe-Ti-O solid solution. Using CO as the carbon feedstock, chemical vapour deposition growth of SWNTs at 800 °C was demonstrated on the Fe-Ti-O catalyst. Nanobeam electron diffraction characterization on a number of individual SWNTs revealed that more than 94% of SWNTs have chiral angles larger than 15°. In situ environmental transmission electron microscopy study was carried out to reveal the catalyst dynamics upon reduction. Our results identify that the phase segregation through reducing Fe-Ti-O catalyst leads to the formation of TiOx-supported small Fe nanoparticles for SWNT growth. The strong metal-support interactions induced by partial reduction of TiOx support promote the wettability of Fe nanoparticle, accounting for the preferential growth of large-chiral-angle SWNTs. This work opens a new avenue for chiral angle selective growth of SWNTs.

In this research, we focused on the development of composite phase-change materials (CPCMs) by incorporation of a paraffin through vacuum impregnation in widely used building materials (Kaolin and ground granulated blast-furnace slag (GGBS)). The composite PCMs were characterized using environmental scanning electron microscopy (ESEM), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques. Moreover, thermal performance of cement paste composite PCM panels was evaluated using a self-designed heating system. Test results showed that the maximum percentage of paraffin retained by Kaolin and GGBS was found to be 18% and 9%, respectively. FT-IR results show that CPCMs are chemically compatible. The phase-change temperatures of CPCMs were in the human comfort zone, and they possessed considerable latent-heat storage capacity. TGA results showed that CPCMs are thermally stable, and they did not show any sign of degradation below 150 degrees C. From thermal cycling tests, it was revealed that the CPCMs are thermally reliable. Thermal performance tests showed that in comparison to the control room model, the room models prepared with CPCMs reduced both the temperature fluctuations and maximum indoor center temperature. Therefore, the prepared CPCMs have some potential in reducing peak loads in buildings when applied to building facade.

Microencapsulated phase-change materials (MPCM) can be used to develop a structural-functional integrated cement paste having high heat storage efficiency and suitable mechanical strength. However, the incorporation of MPCM has been found to degrade the mechanical properties of cement based composites. Therefore, in this research, the effect of carbon nanotubes (CNTs) on the properties of MPCM cement paste was evaluated. Test results showed that the incorporation of CNTs in MPCM cement paste accelerated the cement hydration reaction. SEM micrograph showed that CNTs were tightly attached to the cement hydration products. At the age of 28 days, the percentage increase in flexural and compressive strength with different dosage of CNTs was found to be up to 41% and 5% respectively. The optimum dosage of CNTs incorporated in MPCM cement paste was found to be 0.5 wt %. From the thermal performance test, it was found that the cement paste panels incorporated with different percentages of MPCM reduced the temperature measured at the center of the room by up to 4.6 degrees C. Inverse relationship was found between maximum temperature measured at the center of the room and the dosage of MPCM.

Microencapsulated phase-change materials (MPCM) can be used to develop a structural-functional integrated cement paste having high heat storage efficiency and suitable mechanical strength. However, the incorporation of MPCM has been found to degrade the mechanical properties of cement based composites. Therefore, in this research, the effect of carbon nanotubes (CNTs) on the properties of MPCM cement paste was evaluated. Test results showed that the incorporation of CNTs in MPCM cement paste accelerated the cement hydration reaction. SEM micrograph showed that CNTs were tightly attached to the cement hydration products. At the age of 28 days, the percentage increase in flexural and compressive strength with different dosage of CNTs was found to be up to 41% and 5% respectively. The optimum dosage of CNTs incorporated in MPCM cement paste was found to be 0.5 wt %. From the thermal performance test, it was found that the cement paste panels incorporated with different percentages of MPCM reduced the temperature measured at the center of the room by up to 4.6 degrees C. Inverse relationship was found between maximum temperature measured at the center of the room and the dosage of MPCM.

In this research, we focused on the development of composite phase-change materials (CPCMs) by incorporation of a paraffin through vacuum impregnation in widely used building materials (Kaolin and ground granulated blast-furnace slag (GGBS)). The composite PCMs were characterized using environmental scanning electron microscopy (ESEM), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques. Moreover, thermal performance of cement paste composite PCM panels was evaluated using a self-designed heating system. Test results showed that the maximum percentage of paraffin retained by Kaolin and GGBS was found to be 18% and 9%, respectively. FT-IR results show that CPCMs are chemically compatible. The phase-change temperatures of CPCMs were in the human comfort zone, and they possessed considerable latent-heat storage capacity. TGA results showed that CPCMs are thermally stable, and they did not show any sign of degradation below 150 degrees C. From thermal cycling tests, it was revealed that the CPCMs are thermally reliable. Thermal performance tests showed that in comparison to the control room model, the room models prepared with CPCMs reduced both the temperature fluctuations and maximum indoor center temperature. Therefore, the prepared CPCMs have some potential in reducing peak loads in buildings when applied to building facade.

In this research, we focused on the development of composite phase-change materials (CPCMs) by incorporation of a paraffin through vacuum impregnation in widely used building materials (Kaolin and ground granulated blast-furnace slag (GGBS)). The composite PCMs were characterized using environmental scanning electron microscopy (ESEM), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques. Moreover, thermal performance of cement paste composite PCM panels was evaluated using a self-designed heating system. Test results showed that the maximum percentage of paraffin retained by Kaolin and GGBS was found to be 18% and 9%, respectively. FT-IR results show that CPCMs are chemically compatible. The phase-change temperatures of CPCMs were in the human comfort zone, and they possessed considerable latent-heat storage capacity. TGA results showed that CPCMs are thermally stable, and they did not show any sign of degradation below 150 degrees C. From thermal cycling tests, it was revealed that the CPCMs are thermally reliable. Thermal performance tests showed that in comparison to the control room model, the room models prepared with CPCMs reduced both the temperature fluctuations and maximum indoor center temperature. Therefore, the prepared CPCMs have some potential in reducing peak loads in buildings when applied to building facade.

Microencapsulated phase-change materials (MPCM) can be used to develop a structural-functional integrated cement paste having high heat storage efficiency and suitable mechanical strength. However, the incorporation of MPCM has been found to degrade the mechanical properties of cement based composites. Therefore, in this research, the effect of carbon nanotubes (CNTs) on the properties of MPCM cement paste was evaluated. Test results showed that the incorporation of CNTs in MPCM cement paste accelerated the cement hydration reaction. SEM micrograph showed that CNTs were tightly attached to the cement hydration products. At the age of 28 days, the percentage increase in flexural and compressive strength with different dosage of CNTs was found to be up to 41% and 5% respectively. The optimum dosage of CNTs incorporated in MPCM cement paste was found to be 0.5 wt %. From the thermal performance test, it was found that the cement paste panels incorporated with different percentages of MPCM reduced the temperature measured at the center of the room by up to 4.6 degrees C. Inverse relationship was found between maximum temperature measured at the center of the room and the dosage of MPCM.

In this article, study results of the electrical resistance properties of cement/carbon fiber composite are presented. Using a normal mixing and compacting method, up to 0.85v.% short carbon fiber can be easily incorporated into the cement composite. And its electrical resistivity properties are measured. The resistivity of specimens decreases greatly with the volume fraction of fibers increasing. Moreover, it is found that there is a saturation point for fiber volume fraction. Beyond that, the change of resistivity with the variation of fiber volume fraction becomes much flat. Another interest finding is that the resistivity of the cement materials is a function of frequency of applied voltage. The microstructure associated with the electrical properties of composite is observed. It is possible to apply cement/carbon fiber composite as an electromagnetic shielding composite and so on.

In this article, study results of the electrical resistance properties of cement/carbon fiber composite are presented. Using a normal mixing and compacting method, up to 0.85v.% short carbon fiber can be easily incorporated into the cement composite. And its electrical resistivity properties are measured. The resistivity of specimens decreases greatly with the volume fraction of fibers increasing. Moreover, it is found that there is a saturation point for fiber volume fraction. Beyond that, the change of resistivity with the variation of fiber volume fraction becomes much flat. Another interest finding is that the resistivity of the cement materials is a function of frequency of applied voltage. The microstructure associated with the electrical properties of composite is observed. It is possible to apply cement/carbon fiber composite as an electromagnetic shielding composite and so on.

In this article, study results of the electrical resistance properties of cement/carbon fiber composite are presented. Using a normal mixing and compacting method, up to 0.85v.% short carbon fiber can be easily incorporated into the cement composite. And its electrical resistivity properties are measured. The resistivity of specimens decreases greatly with the volume fraction of fibers increasing. Moreover, it is found that there is a saturation point for fiber volume fraction. Beyond that, the change of resistivity with the variation of fiber volume fraction becomes much flat. Another interest finding is that the resistivity of the cement materials is a function of frequency of applied voltage. The microstructure associated with the electrical properties of composite is observed. It is possible to apply cement/carbon fiber composite as an electromagnetic shielding composite and so on.