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In the present article, the synthesis of TiO2/diazonium/graphene oxide and its photocatalytic activity for methylene blue (MB) degradation have been demonstrated. The functionalization of graphene oxide (GO) with diazonium salt (diazonium-GO) was conducted for enhancing the dispersibility of GO in distilled water. TiO2 was highly dispersed in diazonium-GO to form TiO2/diazonium/graphene. The obtained specimens were characterized by X-ray diffraction, FT-IR spectroscopy, Raman spectroscopy, UV-Vis spectroscopy, scanning electron microscope, transmission electron microscopy, and X-ray photoelectron spectroscopy. It was found that the TiO2 phase in TiO2/diazonium/GO composites can be controlled by adjusting the amount of ethanol or titanium oxide in the reactant mixture. The obtained composites exhibited photocatalytic activities for methylene blue degradation (MB). The composite with ac. 70% anatase can provide the highest MB degradation efficiency. The studying of some intermediates for MB photocatalytic degradation using LC-MS showed that structure of MB by the cleavage and oxidation of one or more of the methyl group substituent on the amine groups lead to form compounds with low molecular masses. Total organic carbon studies confirmed a complete mineralization of MB. The present catalyst was stable and recyclable after three times with a negligible loss of catalytic activity. In addition, the TiO2/diazonium/GO can also photocatalyze for the degradation of some other dyes (phenol, methyl red, and Congo red).

Objectives: The current study was focused on preparation of MgO with the different morphologies for enhanced removals of dyes and heavy metal from wastewaters. Methods/Statistical Analysis: The MgO samples were synthesized by a facile precipitation method with the calcination temperature of 500 °, its morphology was controlled by altering the concentration of K 2 CO 3 and Mg(NO 3 ) 2 . As-prepared samples were characterized by TGA, XRD, N 2 adsorption/desorption isotherm, FT-IR, FE-SEM and TEM. The performance of as-prepared MgO samples was evaluated by adsorptions of dyes and leads (II) and compared to those of commercial MgO (CM-MgO) and Activated Carbon (AC). Findings: Flower-like MgO (F-MgO) had the high surface area and pore volume (232 m 2 /g and 0.575 cm 3 /g, respectively) as compared to rod-like MgO (R-MgO) and CM-MgO. The adsorption rate and adsorption capacity of tartrazine on F-MgO were faster and larger, respectively, than those of R-MgO, CM-MgO and AC. The adsorption of F-MgO was achieved equilibrium in 15 min and the adsorption capacity was 65.8 mg/g at the MgO dosage of 0.12 g, initial tartrazine concentration of 50 mg/L, solution pH of 7.0, and temperature of 30 °C. The adsorption rate was followed the pseudo second equation and the rate constant was 0.02 g.mg –1 .min –1 at 30 °C. The heat of adsorption (ΔH° = 19.48 kJ/mol) confirmed the exothermic adsorption of tartrazine and the negative values of G°indicatedthe spontaneous adsorption. The removal efficiency of tartrazine was gradually decreased, but it still remained at 95.2% for the fifth cyclic experiment. In addition, the removal efficiency of Pb (II) on MgO/tartrazine (95%) was much larger than that of F-MgO (about 10%). Application/Improvements: This study gives promising results in concern with treatment of industrial wastewaters before they are charged into the environment.

In this study, the differential evolution algorithm is used for solving the optimum design problem of composite cellular beams. The design variables are hot rolled profile from which the cellular beam will be produced as well as opening size and its spacing. The objective function is the minimum weight of cellular beam while the design constraints include satisfying the ultimate limit states, the serviceability limit states and the geometric limitations. The design method adopted in this study is based on EN 1994-1-1. Furthermore, a parametric study is conducted to evaluate the influence of beams spacing to the weight of floor beam system. As a result, an optimal spacing of composite cellular beams is proposed. Keywords: composite beam; cellular beam; web opening; steel beam optimization; differential evolution.

The shear transferring mechanisms of shallow-hollow composite beams with concrete slab cast in place are different with conventional headed shear studs and have not been investigated previously. In this study, the behavior and push-out test of concrete dowel connectors for longitudinal shear in shallow-hollow composite beams are described. The theory prediction for concrete dowel connectors without tie-bars adopted in this study was based on EN 1992-1-1 and EN 1994-1-1. Push-out tests of three specimens were conducted and the results were compared with theory prediction and published formula to identify longitudinal shear resistance. The failure of specimens and the ultimate failure load values of push-out test were proved that the behavior of concrete dowel in shallow-hollow composite beams was not under pure shear stress. Keywords: steel-concrete composite beam; shallow-hollow composite beam; concrete dowel connectors; longitudinal shear resistance; shallow floor structure.

This paper presents the results of Nickel component on the microstructure and mechanical properties of the aluminum-copper alloy. With the same heat treatment process (heated to 850oC quenching in water and tempering at 350oC in 2h) noticed: the sample was added nickel, it had phases of nickel with Al and Fe; these phases make sample’s mechanical properties better than the non-nickel sample. The samples were added Nickel, the hardness is higher than those without Nickel (105HRB and 92HRB). The abrasion results show that the Nickel alloyed samples also exhibited better than those without Nickel.

The breakdown due to abrasion and clash of the milling balls made of 13% Cr white cast iron is a complicated process which depends on many factors, especially on the strength of the matrix and carbide phases. As shown, stresses created by abrasion and clash processes are concentrated mainly at the locations such as carbide/matrix boundary and around coarse carbide particles, leading to the cracks and breakdown there. The peeling off carbide particles can be a reason of scratches on the specimen surface. Heat treatment (quenching in oil and tempering at 2500 C for three hours) to transform a soft matrix (austenite) to a harder one (martensite) can be a good solution against abrasion. Concerning the impact, the solution should be the refinement of the carbide particles and their uniform distribution.

Shape memory alloys can return to their original shape by reversible martensitic transformation. The shape memory effect of these alloys has been considered to relate to phase transformation, especially martensite transformation. In the copper-aluminum alloys containing Fe and Ni additives, the relationship between the martensitic transformation and shape memory effect occurs by applying a thermo-mechanical deformation and heat treatment process. This paper presents the phase transformation of the CuAl9Fe4Ni2 alloy that suffered from the deformation and heat treatment process. The samples were heated above 1173°K for homogenization. Then, they were rolled with an appropriate degree of strain to prepare the good conditions for the next steps. They were heated again to 1173°K, then quenched in water to 373°K, and then cooling down in cold water to form martensites with fine grain sizes. Next, the samples underwent cold deformation to create a fine grain in the structure and a favorable distribution for the shape memory process. Finally, the samples were shaped and heated at 843°K to decompose the martensite phase and return to their original shape. The phase transformation and the structure of martensite were determined by modern analytical techniques. The results show that the shape memory level was up to 80%.

Synthetic Aperture Radar (SAR) remote sensing data can be used as an effective alternative to detect surface water and provide useful information regarding operational flood monitoring, in particular for the improvement of rapid flood assessments. However, this application frequently requires standard and simple, yet robust, algorithms. Although thresholding approaches meet these requirements, limitations such as data inequality over large spatial regions and challenges in estimating optimal threshold values remain. Here, we propose a new method for SAR water extraction named Hammock Swing Thresholding (HST). We applied this HST approach to four SAR remote sensing datasets, namely, Sentinel-1, ALOS-2, TerraSAR-X, and RadarSAT-2 for flood inundation mapping for a case study focusing on the Tam Nong district in the Vietnam Mekong delta. A 2D calibrated Hydrologic Engineering Centers River Analysis System (HEC-RAS) model was coupled with the HST outputs in order to estimate the optimal thresholds (OTs) where the SAR-based water masks fitted best with HEC-RAS&rsquo, s inundation patterns. Our results showed that water levels extracted from Sentinel-1 data best agreed with the HEC-RAS water extent (88.3%), following by ALOS-2 (85.9%), TerraSAR-X (77.2%). and RadarSAT-2 (72%) at OTs of &minus, 15, 68, 21, and 35 decibel (dB), respectively. Generated flood maps indicated changes in the flood extent of the flooding seasons from 2010 and 2014&ndash, 2016 with variations in spatial extent appearing greater in the TerraSAR-X and RadarSAT-2 higher resolution maps. We recommend the use of OTs in applications of flood monitoring using SAR remote sensing data, such as for an open data cube (ODC).

This paper analyzes mode choice behavior in different weather conditions, with population groups, on travel purposes and travel distances to support the formulation of weather responsive traffic management measures. Revealed and stated adaptation surveys are carried out with 400 respondents and 100 respondents, respectively. The survey shows that the rate of mode change due to adverse weathers is much smaller than the figure in developed countries. The major patterns of mode change are shifts from motorcycle to car or taxi, accounted nearly half of mode changes, thus causing severer traffic congestions. The mode choice modelling show travel time, travel cost, gender, income, specific jobs, motorcycle ownership, bus ticket holding, provision of weather information prior to the trip are significant factors to mode choice decision under bad weather conditions. The results suggest focusing on “avoid or reduce unnecessary mobility demand” and “improve public transport” measures.

Nonisothermal glass molding has recently become a promising technology solution for the cost-efficient production of complex precision glass optical components. During the molding process, the glass temperature and its temperature distribution have crucial effects on the accuracy of molded optics. In nonisothermal molding, the glass temperature is greatly influenced by thermal contact conductance because there is a large temperature difference between the glass and mold parts. Though widely agreed to be varied during the molding process, the contact conductance was usually assumed as constant coefficients in most early works without sufficient experimental justifications. This paper presents an experiment approach to determine the thermal contact coefficient derived from transient temperature measurements by using infrared thermographic camera. The transient method demonstrates a beneficially short processing time and the adequate measurement at desirable molding temperature without glass sticking. Particularly, this method promises the avoidance of the overestimated contact coefficients derived from steady-state approach due to the viscoelastic deformation of glass during the inevitably long period of holding force. Based on this method, the dependency of thermal contact conductance on mold surface roughness, contact pressure, and interfacial temperature ranging from slightly below-to-above glass transition temperature was investigated. The results reveal the dominance of interfacial temperature on the contact conductance while the linear pressure-dependent conductance with an identical slope observed for all roughness and mold temperatures. The accurate determination of the contact heat transfer coefficients will eventually improve the predictions of the form accuracy, the optical properties, and possible defects such as chill ripples or glass breakage of molded lenses by the nonisothermal glass molding process.

This paper presents descriptive analyses to investigate the transferability of FEATHERS, an activity-based travel demand model developed for Flanders (Belgium), a region in a developed country to Ho Chi Minh City (Vietnam), a metropolitan area of a developing country using personal and household travel survey data. The transferability was tested by using indicators which represent individuals' activity and travel behaviors. The results confirm the transferability of FEATHERS modelling structure to Ho Chi Minh City (HCMC), but all sub-models require recalibration due to the different cultural settings between the two study areas. The differences in transport mode options, land use patterns and individuals' location choice preferences make transport mode and location choice the least transferable models. (C) 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the Conference Program Chairs. We would like to thank the JICA study team for their provision the data of METROS project. Linh, HT (corresponding author), UHasselt Univ Hasselt, Transportat Res Inst IMOB, B-3590 Diepenbeek, Belgium ; Univ Transport & Commun, Dept Civil Engn, Hanoi, Vietnam.