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The aldose reductase (AR) enzyme is considered a potential target for the management of diabetic complications. In this study, we describe the binding and enzyme kinetics of AR by naringenin, a bioflavonoid present in many dietary sources. Naringenin showed an inhibitory effect on the activity of AR with an IC50 value of 2.6 μM in an uncompetitive manner. Binding studies confirmed that the naringenin-AR complex has high spontaneous affinity (Ka = 1.94–7.88 × 104) with negative ΔG° value (−5.78 kcal mol−1). The interaction was enthalpy driven and the microenvironment of aromatic residues of AR was also altered. Various stages of protein oxidation and glycation were also measured. Naringenin inhibited fructosamine content by approximately 31.6% at 10 μM, and at the same concentration, >93% inhibition of fluorescent advanced glycation end-products (AGEs) was achieved. There was a significant recovery in free thiol groups and carbonyl content of bovine serum albumin (BSA). Furthermore, molecular docking of naringenin with AR revealed that naringenin formed two hydrogen bonds (Asn160 and Ile260), and three Pi-Pi interactions (two with Trp20 and one with His110). This study provides molecular insight of naringenin-AR interaction and mechanism of antiglycation which may be useful in the development of inhibitors for AGEs formation.

The objective of this paper is to establish the state of knowledge on fast pyrolysis of bio-oil and bio-asphalt binder and to facilitate efforts in improving the overall performance of bio-asphalt and maximizing its road application. On the basis of reviewing the relevant literature recently, the fast pyrolysis (FasP) preparation process of bio-oil and its main properties, the preparation process of bio-asphalt and its performance and the application of bio-asphalt have been summarized. Due to the variations in raw materials, the adopted methods of FasP to prepare bio-oil could be different, and the properties of bio-oil from different sources are also different. At present, the plant-based bio-oil (mainly derived from wood waste and sawdust) has been widely used to prepare the bio-asphalt. Research on the low-temperature flexibility, high-temperature rheology, workability and other performance of biological asphalt showed that the workability and high-temperature performance of most asphalt are improved after adding bio-oil. However, the low-temperature performance is found to relatively reduce. Also, with regards to its application as a rejuvenator, bio-oil can considerably rejuvenate the aged asphalt's mixture performance. By far, most of research on bio-asphalt is still focused on the performance of bio-asphalt binder in the laboratory; its application in practical road engineering is still to be examined. This review also provides an outlook for the future, for example, establishing an integrated preparation process from bio-oil to bio-asphalt, and evaluating the properties of bio-asphalt by new standards. Keywords: Road engineering, Bio-oil, Bio-asphalt, Preparation process, Performance, Application of bio-asphalt

The consistency of the ethanol foamed binders and mixtures prepared using asphalt binders foamed by the manual injection technique and laboratory foaming device were evaluated and compared in this study. The asphalt binders foamed using both methods was prepared at 120 °C, 130 °C and 140 °C. The performance of ethanol-foamed binders was evaluated in terms of rotational viscosity, expansion ratio, and low temperature cracking. Meanwhile, the performance of foamed WMA mixtures was tested using semi-circular bending (SCB), disk-shaped compact tension (DCT), and tensile strength ratio (TSR) tests. In order to conduct the TSR test, the samples were conditioned using the Moisture Induced Stress Tester (MIST) to simulate the pore pressure and scouring effects due to a tire passing over wet pavement. The foamed WMA mixtures were produced using pre-heated aggregates at 80 °C and 100 °C and foamed asphalt binders produced at 130 °C. The nano-hydrated lime was used as the filler and anti-stripping agent. Overall, the properties of ethanol-foamed binders and WMA mixtures produced via both methods are significantly comparable, except the resistance to moisture damage test result. However, the findings indicate that the ethanol-foamed WMA mixtures prepared using both techniques are having good resistance to moisture damage, based on the TSR values more than 0.8. The foamed WMA mixtures also exhibited a better resistance to cracking, as indicated by a higher tensile strength compared to the control HMA. Additionally, the WMA specimen prepared at 100 °C was less susceptible to rutting than the samples produced at 80 °C. Keywords: Warm mix asphalt, Foaming technique, Rheological, Foam quality, Mixture performance

Fog seal with sand (FSS) became a promising technique for the preventive maintenance of flexible pavements. However, there is no quick and effective test method to evaluate whether it is possible to open the road to traffic shortly after the rehabilitation work. This study aims to introduce a new evaluation method to confirm the exact traffic opening time. In this paper, experimental works were performed based on the empirical tests, in terms of penetration, ductility, softening point, viscosity, permeability, and sand optimization tests to determine the best material. Evaporation and load abrasion tests were conducted to attain essential information that will help in establishing the new evaluation method and standard. Meanwhile, Damping test was conducted to prepare the stained pad specimens for the image analysis using Image Processing Technology (IPT). Results show that Material C (from SealMaster) had the best performance of rejuvenation and permeability. In addition, when the application rate ranged from 1.4 kg/m2 to 1.68 kg/m2 and the temperature interval ranged from 20 °C to 40 °C, it took four hours or more to complete the curing process. Finally, 2% of the stained pixel was confirmed as a terminal condition. A standard protocol based on the damping test and IPT has been established to decide the exact curing time required prior to opening the road for traffic.

The objective of this study is to characterize the foamed asphalt binders prepared using different combinations of physical and chemical foaming agents. The foamed asphalt binders were investigated using the Rotational Viscosity (RV), Dynamic Shear Rheometer (DSR) and expansion ratio tests. Asphalt binders were also evaluated after short-term and long-term aging conditions. During the asphalt binder’s foaming process, the preheated binder was formerly foamed using a physical foaming agent (either water or ethanol), followed by the addition of sodium bicarbonate (NaHCO3) to improve the bubbling and the stability of the foam. Theoretically, through this process, numerous bubbles are generated by the vaporized ethanol or water, and the gases are released by NaHCO3, which significantly increases the volume of foamed asphalt. All foamed asphalt binders were produced at the same temperature, 100 °C, to diminish the inconsistency of binder-aging conditions during the preheating process. Overall, the results indicated that ethanol has better characteristics in lowering the viscosity of asphalt binders at low temperatures and is expelled from the asphalt binder after continuous heating at temperatures higher than its boiling point (78 °C). Although the addition of NaHCO3 has slightly increased the foamed binder viscosity that may affect its workability, it substantially lowers the volatile loss of foamed binders, as well as significantly improves the expansion ratio and the resistance to rutting.

This paper analyzes the impact of COVID-19 pandemic situation on residential loads and local distribution transformer. The transformers’ operating conditions in terms of hottest winding temperature, top oil transformer, loss of life (%LOL) are analyzed considering different loads and harmonics content in the transformer currents. Based on these analyses, safe operating conditions of transformer are derived. Six types of consumers having different consumption patterns and different type of residential loads are considered for the analysis. In order to mitigate the adverse impacts of COVID-19 on loads and distribution transformer, the use of behind-the-meter (BTM) photovoltaic (PV) source, battery energy storage and electric vehicle, load scheduling, and less utilization of loads that have distortion factors during office hours are proposed. A performance comparison has been made without and with considering the proposed BTM solution, load scheduling and loads having distortion factors. Simulation results show that, due to lockdown situation of COVID-19 issue, the residential loads consumptions increase during office hours and hence the local distribution transformer gets affected. Also, the proposed BTM solution, load scheduling and less utilization of loads having harmonic distortion can cope up with the increased energy consumptions during office hours.

Eggshell concrete is an innovative green material that helps to recycle eggshell waste while reducing the environmental harm caused by excessive cement production. However, recent studies on eggshell concrete are limited and the outcomes may vary due to the variation of mix design. Design of experiment is used to simplify and optimize the study of sustainable concrete, yet analysis involving eggshell concrete is still scarce. This paper aimed to develop mathematical models for the prediction of eggshell concrete compressive strength using the mixed regression (MR) and response surface methodology (RSM). Overall, 43 datasets were collected from available studies in the literature on eggshell powder as partial cement replacement. The input variables used were percentage of eggshell, percentage of Ground Granulated Blast-furnace Slag (GGBS), cement content, fine aggregate, coarse aggregate, water, and Conplast SP-430 superplasticizer. The analysis of contour plot concluded that eggshell powder increased the concrete compressive strength at an optimal replacement percentage between 5% and 10%. However, the cement partial replacement with eggshell powder is more optimal for mix design with higher water content. The statistical results of the model, such as R2, adjusted R2 and root-mean-square error (RMSE), indicated that both MR and RSM models are powerful tools to formulate and predict the eggshell concrete compressive strength. However, RSM models showed better accuracy and lower deviation.

In Hungary, successive steps have been taken toward adjusting GHG emissions from all sectors on a national scale. However, few studies were carried out to analyze the environmental dimensions of GHG emissions from an economic point of view. In this research, the contemporary changes of GHG emissions between 1985 and 2018 were analyzed using the Mann-Kendall test (M-K test); along with the interaction between GHG emissions and economic growth by applying the environmental Kuznets curve (EKC). Results showed that the industrial sector has been the main source of CO2-emitting, and contributed 72% of the total emissions. Meanwhile, the biggest CH4-emitting sector was the waste sector (44%), followed by the agricultural sector (39%). Nonetheless, the agricultural sector was responsible for more than 65% of N2O emissions over Hungary. The M-K test results showed that total CO2 emissions were reduced significantly (p

Natural rubber (NR) is widely used in the industry to produce various products. It requires excellent physical, mechanical and thermal properties to prolong its performance for indoor and outdoor applications. Different sulphur vulcanization systems such as conventional vulcanization (CV), semi-efficient vulcanization (SEV) and efficient vulcanization (EV) systems have different sulphur intake thus give different cross-link density (CLD) and subsequently end properties of the NR vulcanizate. To conserve natural resources, industrial waste such as waste latex compound (WLC) can be utilized to form rubber-rubber blend with the NR. In this study, the effect of different vulcanizing system on the properties of SMR-L/WLC blend was investigated. By comparing the properties of 75:25 SMR-L/WLC blend with 100:0 SMR-L/WLC blend, the effect of WLC loading was also studied. Generally, 100:0 and 75:25 SMR-L/WLC blend with CV system has the best physical and mechanical properties in tensile strength, elongation at break, M100, M300 and hardness. This is due to higher polysulphidic cross-links in CV system which facilitate structural networks rearrangement. This enable the test specimens to withstand higher force. For heat retention properties, both blends showed EV system has better heat retention properties. EV system consists of mainly monosulphidic cross-links with higher thermal stability because the monosulphidic bond is stronger than the polysulphidic bond. The loading of WLC has affect the end properties of rubber vulcanizate. In general, WLC improved the physical and mechanical of vulcanizate but may improve or deteriorate the heat retention. WLC is partially vulcanized rubber thus, presence of WLC lead to higher crosslink density. However, during heat ageing test, the structural changes of the blend vulcanizate results in lesser changes in M100 and M300 but more changes in tensile strength and elongation at break. As conclusion, there is an optimum rubber vulcanizate properties need to be obtained by either using different sulphur vulcanization system or the WLC to have a balance in physical, mechanical and thermal properties.

The foaming techniques implemented in Warm Mix Asphalt (WMA) have been highly recognized to aid in the production of eco-friendly asphalt mixtures. However, to a certain extent, the application of this technology is limited by its defects in moisture sensitivity and rutting resistance. Prior to this, the WMA mixtures were prepared using ethanol and ethanol-NaHCO3 foamed binders and were tested to evaluate their moisture susceptibility, rutting potential, crack resistance and thermal cracking potential. The mixture samples were prepared based on the mixture design for a 9.5 mm nominal maximum aggregate size. The designed traffic level was less than 3 million Equivalent Single-Axle Loads (ESALs). Nano-hydrated lime was incorporated during the preparation of the sample as a filler material. The foamed WMA mixtures were prepared at three different temperatures: 80 °C, 100 °C and 120 °C; meanwhile, the control Hot Mix Asphalt (HMA) sample was prepared at 155 °C and 145 °C. For the purpose of incorporating the temperature losses during the foaming process, the foamed binders were produced at a temperature higher than the production temperatures by approximately 20 °C. Overall, the results show that 1% and 3% ethanol-foamed WMA mixtures are found to have a comparable or better performance than the control HMA mixture, especially for the samples prepared at 120 °C. The addition of nano-hydrated lime contributed to the increase on the adhesive and cohesive characteristic of mixtures; hence, improving the resistance to moisture damage. Regardless of the contents of the foaming agent and production temperatures, most of the foamed WMA mixtures prepared using a combination of foaming agents have comparable thermal cracking characteristics as the control HMA mixture. The resistance to rutting of foamed WMA mixtures increased with the increase in the production temperatures. The sample prepared at 120 °C is found to have much lower or comparable rut depths to the control HMA mixture. However, the combination of ethanol with 1% NaHCO3 was optimal for these foamed WMA mixtures prepared at 80 °C to obtain a good long-term performance.

Asphalt binders and mixtures are more susceptible to permanent deformation at high temperature. The Dynamic Shear Rheometer (DSR) test results have been extensively used to evaluate the effects of wax and foamed warm additives on asphalt binder properties at elevated temperature. Wax based additives improve the rheological properties of the binders at high temperatures, while foamed based additives exhibit no significant effects on binder rheology. However, the literature reports contradictory effects of surfactant-wax warm additive named Rediset, on binders and mixtures propertiesat high temperatures. Some studies reported positive effects, while others found otherwise. This paper evaluates the effects of binder type, additive content and loading type on high temperature properties of warm asphalt binders incorporating Rediset on temperature, strain, frequency and stress sweep tests as well as flow, creep, multiple stress creep and recovery and zero shear viscosity test results. The results showed that the effects of Rediset depended on binder type, additive content and loading type. It implies that the chemical composition of different dosage of this warm additive with various binder types, directly affect the performance of binders subjected to various loading types at high temperatures. Hence, simply relying on one type of shear loading in the DSR test for evaluating the high temperature properties of binders incorporating a surfactant-wax additive, can lead to erroneous conclusions.

The microstructure characteristic of asphalt mixture has substantial effects on its macroscopic mechanical properties. The study on the structural characteristics of asphalt mixtures involving the microscopic scale has rarely been considered. This study investigates the effects of the angularity of coarse aggregate on the microstructure of two commonly practiced asphalt mixture gradations (AC-16 and SMA-16) based on the X-ray Computed Tomography (XCT). Three-dimensional angularity was introduced based on the XCT images. Four indicators including average contact point number (ACN), average contact length (ACL), average vertical contact index (AVCI) and average horizontal contact index (AHCI) were proposed to evaluate the skeleton contact characteristics within the asphalt mixture through iPas. The volume of air voids, equivalent diameter and roundness were used to characterize the void characteristic of the asphalt mixtures with different angular aggregates by the analysis of Image-Pro Plus (IPP). The results indicate that the three-dimensional angularity (3DA) could characterize the angularity of coarse aggregate. The angularity has a significant influence on the skeleton contact characteristics of asphalt mixture, whereas a lower angularity has resulted in weaker skeleton contact characteristics. A skeleton contact characteristic of SMA-16, with a dense coarse aggregate structure, is stronger than AC-16, which belongs to the dense suspension structure. The shape of the voids at the top and bottom of the asphalt mixture specimen is the most complex and irregular, while the shape of air voids in the middle section of the specimen is simple and regular. This study could provide support for the further research and application of microscopic properties of asphalt mixtures.

Design of ultra-low power SRAM with robust operation for Internet of Thing (IoT) sensor node is a new challenge. In this work, a novel 9T TFET based SRAM bit cell is proposed. The analysis and simulation results demonstrate that the proposed cell eliminates read disturb issue and outperforms the state-of-the-art 9T TFET bit cell in terms of static and dynamic write performance. The presented circuit topology incorporates power cut-off and write ‘0’ only technique to enhance the write performance. The proposed cell exhibits 1.15× higher write margin (WM), 25% lower write delay, consumes 73% (57%) lower write (average) energy, 7% smaller standby leakage power measured at VDD = 0.3 V. The proposed cell also shows significant improvement in the read/write performance as compared with existing 7T and 8T TFET cells. Our proposed cell also eliminates half-select disturb issue to make it suitable for bit-interleaving architecture that is a must for enhanced soft error immunity.

In this study, the effect of fly ash (FA) as an alternative filler mineral was evaluated regarding workability, structural performance, durability, and its sustainability when prepared using hot (HMA) and warm mix asphalt (WMA) technologies. The results revealed that workability of HMA and WMA samples containing FA are comparable to the mixes containing cement powder, yet the WMA mixes containing 4% Sasobit® prepared at 145 °C exhibited the highest workability, regardless of filler type. However, the compaction energy index (CEI) of WMA samples containing FA is more sensitive to the Sasobit® content variations at each mixing temperature. Besides, use of FA as an alternative filler mineral increased the resilient modulus up to 7.5% as compared to HMA and WMA containing cement powder. The tensile strength ratios of asphalt mixtures containing FA are not only satisfied the design criteria, but it is also higher than those of samples with cement filler. Use of WMA technology improves sustainability in the construction phase, while incorporation of FA filler decreases the greenhouse gas emissions during the raw material manufacturing stage. Therefore, synergistic effects of using the WMA technology and FA improve the sustainability of both construction and raw material processing within the cradle to gate phases. In conclusion, a higher workability and resilient modulus test result together with less environmental emission indicate that the WMA technology using Sasobit® and FA as an alternative filler are showing great potential for the production of eco-friendly asphalt pavement.

This paper presents an alternative method for developing a laboratory short-term ageing procedure for binders that corresponds to the asphalt mixture production practices carried out in a tropical region. In this method, the ASTM D2872 procedure was adapted to artificially short-term age asphalt binders, while ageing time and ageing temperature were evaluated. A statistical technique named response surface method (RSM) was used for the design of experiment, analysis of the test results from the field and laboratory samples, and selection of an appropriate laboratory protocol. An experimental matrix was designed based on the central composite method for two basic independent laboratory factors: ageing times in a range of 85–175 min, and ageing temperatures within 148–178 °C. Several test variables, include softening point, penetration, G∗/sin δ at 64 °C and rotational viscosity at 135 °C of three conventional binders were considered as dependent test factors (responses). The responses were analyzed using RSM to derive mathematical equations, while the corresponding time and temperature were determined from optimization of the test results. The outcome of this study indicated that the conventional short-term ageing protocol in accordance with the ASTM D2872 may not be sufficient to simulate the short-term ageing of asphalt binders in the Malaysian weather condition, where high daily temperatures, humidity, and ultraviolet are concerned. Based on the statistical analyses, both time and temperature have significantly affect the physical and rheological properties of short-term aged binders. Overall, all three binders show quadratic models for the resulting responses with the exception of two binders which show 2FI and linear models for its physical properties. The resulting optimization recommends a short-term ageing procedure at 170 °C for 135 min to appropriately mimic the field binder properties under Malaysian climate.

This paper presents a pseudo differential 12 transistor (PD12T) ultra-low leakage, fully half-select-free robust SRAM cell with good static and dynamic read/write performance. The proposed cell offers best Read/Hold SNM, Write Margin (WM) and least leakage power among all the cells considered in this work while causing an area overhead of 2.5× of that of 6T cell. Simulation results at VDD = 0.5 V show that PD12T cell offers 4.24× higher RSNM, 1.62× higher WM, 1.9× smaller leakage power (at 50 °C) as compared to 6T SRAM. The proposed cell offers VDD,min = 140 mV which is 260 mV smaller than that for 6T cell. When operated at VDD,min, the proposed cell consumes 13.6× smaller mean leakage power. The Ion/Ioff ratio of the proposed cell is more than 10× as compared to 6T cell and it holds potential to compensate for the area overhead by having more number of cells connected to the same bitline. The proposed cell is also suitable for all-TFET implementation as it requires only unidirectional current flow through transistors. Monte Carlo simulations using HSPICE with 16 nm PTM were performed by incorporating local and global variations and it is observed that the proposed cell offers high robustness against PVT variations. The proposed cell has highest critical charge among all other considered cells, which means that it is least vulnerable to soft-errors. The proposed PD12T also offers the best Electrical Quality Metric (EQM) among the cells considered in this work. The MC simulations for HSNM of row and column half-selected cells show that the mean value of SNM is approximately 30% of VDD. Therefore, the proposed cell can be used for bit-interleaving architecture to achieve multi-cell upset immunity and could be a good choice for applications that demands high stability, moderate speed and ultra-low power.