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Experimental data is often corrupted by measurement noise in practical engineering and there are multiple observed data under the same experimental condition. The noisy measurement data can be considered as the response of an underlying stochastic dynamical system. To explore the response properties from noisy measurement data with the partial information of the given stochastic dynamical system, a novel method named as the stochastic generalized cell mapping with deep learning (SGCM-DL) is proposed based on the idea of the image processing. Noisy measurement data is reconstructed into a matrix to be expressed by the image, which is used as the training data of the neural network. The obtained neural network agent model is combined to reveal properties of the underlying stochastic dynamical system and employed to predict stochastic responses with given initial values by the way of the image generation. The technique of the image super-resolution (SR) is introduced to generate the image with higher resolution from the output image of the neural network. Based on the image with higher resolution, one-step transition probability matrix with the larger dimension is obtained for stochastic dynamical systems. Then probability density functions (PDFs) of transient and stationary responses can be obtained by the proposed method in this paper. Several examples are presented, and the good effectiveness and time-saving are observed. • Explore the response properties from noisy measurement data with partial information for given stochastic dynamical systems. • A novel method is proposed based on the idea of the image processing, named as SGCM-DL method. • The training data of the neural network is reconstructed into a matrix to be expressed by the image. • Combining the technique of image super-resolution, transient and stationary responses are obtained. • The numerical results show the good effectiveness of the SFCM-DL method. [ABSTRACT FROM AUTHOR]

The adsorption of NO and NH 3 gaseous molecules on Mn 3 O 4 /TiO 2 catalysts is studied based on density function theory and the corresponding experiments for low-temperature SCR of NO x by ammonia. The SCR performances of the Mn 3 O 4 /TiO 2 catalysts prepared by joint precipitation method were systematically carried out in the temperature range of 90–300 °C. The results show that nitrogen oxide can first adsorb on the manganese-terminal to form nitrates species, and then NH 3 are more inclined to adsorb on Brønsted acid sites. Bridging nitrate and bidentate nitrate can be turned into monodentate nitrates, and NH 4 + was formed when there is ammonia and water molecules because the adsorption and dissociation of the water on the surface of the catalyst is the main source of hydroxyl groups. It is indicated that L-H mechanism plays a major role in NH 3 -SCR process. [ABSTRACT FROM AUTHOR]

The poisoning of alkali metal on MnO x /TiO 2 catalysts used for selective catalytic reduction (SCR) of NO x by NH 3 was investigated. KNO 3 , KCl and K 2 SO 4 were doped on MnO x /TiO 2 catalysts by sol–gel method, respectively. The SCR activity of each catalyst was measured for the removal of NO x with NH 3 in the temperature range 90–330 °C. The experimental results showed that catalyst with KNO 3 have a stronger deactivation effect than other catalysts. The properties of the catalysts were characterized by XRD, BET, SEM, XPS, H 2 -TPR, NH 3 -TPD and in situ DRIFTS analyses. The characterized results indicated that KNO 3 , KCl and K 2 SO 4 caused the similar decrease of specific surface area and pore volume, but the quantity of acid sites for KNO 3 -MnO x /TiO 2 catalyst reduced sharply. The main reason for catalyst deactivation is attributed to two aspects: one was physical influences for the decrease of surface area and pore volume, another was chemical influences that the K + ions decomposed by KNO 3 neutralized Brønsted acid sites of catalyst and reduced their reducibility. The chemical influence played a leading role on the deactivation of catalysts. [ABSTRACT FROM AUTHOR]

• Providing references for the application of mineral polarization effect to the field of denitration catalysis. • A microcosmic mechanism for tourmaline affecting denitration catalytic material is proposed. • Under the action of electric field, the band gap of catalyst become narrower, the gas delocalization is enhanced. Development of the efficient MnO x /TiO 2 catalysts with high dispersibility and stability of denitration reaction for NH 3 -SCR is crucial to control NO x emission at low temperature. Herein, we propose mineral polarization effect modification on the surface of MnO x /TiO 2 denitration catalytic material via coprecipitation method using tourmaline as modifying agent, and evaluate its performance of NO x removal. Particularly, tourmaline-MnO x /TiO 2 catalysts presented a high denitration rate about 97% under the condition of 1000 ppm NO, 1000 ppm NH 3 and 5% O 2 at 200 °C and maintained above 91% removal efficiency within 10 h, which was mainly ascribed to the polarization effect of tourmaline. The doping of tourmaline could improve the dispersion of catalytic materials, reduce the band gap width, and promote the activation of NH 3 and the oxidation of NO. Moreover, the microscopic mechanism was studied by density functional theory (DFT) calculation from the aspects of adsorption energy, mulliken charge and density of states during the adsorption process. Overall, the results of this study will provide references for the application of mineral polarization effect to the field of denitration catalysis and promotes the further understanding of the mechanism for deNO x reaction process. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights: [•] Catalysts of Mn-Ce-M/TiO2 (M=Fe, Ni) prepared by co-precipitation method for low temperature selective catalytic reduction (SCR). [•] Using carbamide solution, ammonia and hydrogen peroxide as precipitation agents, showed good activity in low temperature and resistance performance of K+ cation (K/Mn=0.5). [•] Poisoning mechanism occurs via chemical bonding of the K+ cation to the M OH sites, the so-called Brønsted acid sites. [ABSTRACT FROM AUTHOR]

• The construction of inherent reactive XPSF surface by ultraviolet-zone. • The fabrication of covalently bonded XPSF/mortar interfaces. • The thorough investigation of the reactions between APTES and XPSF surface. The inert surface of extruded polystyrene foams (XPSF) was activated by ultraviolet-ozone (UVO) for the first time to improve the interfacial compatibility with mortar. From the structural analysis (X-ray photoelectron spectroscopic (XPS) and contact angle (CA)), it was suggested that a 10 min UVO exposure was efficient enough to introduce oxygen-contained elements (such as carboxyl groups) upon the obtained UVO-XPSF surface, leading to the increased bonding strength (BS) from 0.058 MPa of neat XPSF/mortar composites to 0.088 MPa. Then, 3-aminopropyl triethoxysilane (APTES) was selected as the promoter to further enhance the BS value of XPSF/mortar composites. The presence of the silane was confirmed by CA, Fourier transform infrared-attenuated total reflection (FTIR-ATR) and XPS. By optimizing the reaction conditions (activation and reaction time: 7 and 3 min, concentration of APTES: 2% and pH value of the silane solution: 10), a maximum BS of 0.168 MPa could be obtained. Through the mechanism analysis, it was demonstrated that APTES acted as a chemical bridge that covalently jointed XPSF by the formation of amide peptide and inorganic mortar by the condensation of silanols. [ABSTRACT FROM AUTHOR]

Abstract: As the sign of social development, the vehicles and traffic flux have been increasing and have greatly influenced the ecological environment. The soil and snow samples which collected on the Songyu Road in Beijing were studied in the present investigation with ICP, and the contents of Pb and Zn with different soil depth and different time were analyzed. Based on the analyzing the condition of the roads, rainfall and so on, the serious pollution of heavy metals on the road in Beijing was described. Finally the method to prevent from the heavy metal contamination by porous cementations materials was discussed. [Copyright &y& Elsevier]

• KT could enhance As uptake in fronds of two plants. • KT promoted the growth of the two plants. • KT can significantly increase SOD and CAT activities in two plants. • KT contributed to As tolerance in plants under different As species stress. Cytokinins (CTKs) enhance plant tolerance to heavy metals, but the associated mechanisms are not yet fully understood. Here, we investigated the effects of kinetin (KT, a type of CTKs) on arsenic (As) speciation and antioxidative enzymes in plant fronds, by comparing Pteris cretica var. nervosa (As hyperaccumulator) and Pteris ensiformis (non-hyperaccumulator). A hydroponic test was carried out and the two plant species were treated with 2 mg L−1 arsenite [As(III)], arsenate [As(V)] or dimethylarsinate (DMA), and then 0–1.0 mg L−1 KT was exogenously applied for 14 days. The maximum As uptake of the two experimental plants was 0.5 mg L−1 KT. Fresh plant biomass was also significantly increased, except in P. cretica var. nervosa under DMA stress. The frond superoxide dismutase (SOD) and catalase (CAT) activity in the two plant species was significantly increased by 0.5 mg L−1 KT. Additionally, a significant decline in frond peroxidase (POD) activity was observed in P. ensiformis at 1.0 mg L−1 KT under As(III) stress. However, POD activity was significantly increased in P. cretica var. nervosa , at 0.1 mg L−1 KT, under As(III) or DMA stress, and at 1.0 mg L−1 KT, under As(V) stress. Therefore, KT promoted As transport and increased frond POD activity in P. cretica var. nervosa , which contributed to its As tolerance under stress from different As species. [ABSTRACT FROM AUTHOR]

Tertiary alkanolamines play an essential role in the hydration of cement-based materials as one of the main components of cement grinding aids and concrete admixtures. Although the field has been well-studied, the significant effects of slight variations in alkanolamine type and dosage make it imperative for researchers to fully understand alkanolamines before using them. Therefore, it is necessary to understand in detail the mechanism of different alkanolamines affecting the hydration of cement-based materials and their effects on setting and hardening. Based on the synthesis and chemical characteristics of alkanolamines, the complexation between alkanolamine and metal ions is discussed in this paper. The influence of alkanolamines on hydration of cement-based materials and the role of complexation in hydration are studied. Various properties of cement-based materials in the presence of alkanolamines are rigorously reviewed. The synergistic effects of alkanolamine and other admixtures are also considered in this review. The research findings prove that the complexation of alkanolamines plays an essential role in hydration and further interferes the microstructure and properties of the cement-based materials. Variations in the molecular structure and dosage of alkanolamines can lead to significant differences in hydration. The modification of alkanolamines at the molecular level and their use in combination with other admixtures are the future research directions. The working mechanism of alkanolamines in the hydration process of cement-based materials still needs to be further explored. • Complexation of alkanolamines significantly affects cement hydration. • Different alkanolamines have different effects on mineral phase hydration. • Alkanolamines significantly affect the morphology of C-S-H gels and Ca(OH) 2. • The right dosage of alkanolamine could improve compressive strength. • TEA has a significant effect on setting time. [ABSTRACT FROM AUTHOR]

Steel slag (SS) as a supplementary cementitious material has low cementitious activity. Diethanol-isopropanolamine (DEIPA) is an organic admixture that can enhance the cementitious activity of cementitious materials. This work aimed to investigate the hydration characteristics of SS under the complexing of DEIPA. The hydration process of SS, the complexation of DEIPA with metal ions, and the dissolution process of C 3 A and C 3 S in the presence of DEIPA were systematically investigated. The results showed that DEIPA enhanced the hydration of aluminate (C 3 A and C 12 A 7), ferrate (C 2 F) and silicate phases (C 3 S and C 2 S), which formed a large amount of monocarboaluminate, paraalumohydrocalcite and C–S–H gels. In the early stages of hydration, the hydration products were mainly C–S–H gels, monocarboaluminate and paraalumohydrocalcite, and in the later stages of hydration, the hydration products were mainly C–S–H gels, paraalumohydrocalcite. The monocarboaluminate may be transformed to paraalumohydrocalcite at a later stage. This hydration-promoting effect was related to the complexation of DEIPA. DEIPA facilitated the dissolution of mineral phases and the precipitation of complexed metal ions by complexing with metal ions. The stronger complexation of Al3+ by DEIPA made it more solubilizing for C 3 A. As a result, more aluminum-containing hydration products were formed. The weaker complexation of Ca2+ by DEIPA made it a weaker solubilizing for C 3 S, which also led to a weaker promotion of silicate hydration by DEIPA. The solubilization of DEIPA to minerals enhanced the cementitious activity of SS, which ultimately led to the increase in the compressive strength of the hardened SS paste at each age. [ABSTRACT FROM AUTHOR]

The impact on hydration of four kinds of alkanolamines (triethanolamine (TEA), triisopropanolamine (TIPA), diethanol-isopropanolamine (DEIPA) and methyldiethanolamine (MDEA)) in a steel slag cementitious system was reviewed. Isothermal calorimetry studies provided information on the hydration heat release rate and the cumulative energy released by blend cement systems. Mortar strength, quantitative X-ray diffractometry, mercury intrusion pore size distribution analysis, scanning electron microscopy and thermogravimetric analysis were used to analyze the mechanism of strength enhancement and micro-structure of hydrates that were impacted by alkanolamines. Alkanolamines prolonged the hydrated induction period in the steel slag–cement system, and enhanced the second exothermic peak of hydration at dosages of 0.01%, 0.03% and 0.05%. The second hydration rate was decreased by TEA, DEIPA and MDEA, and increased by TIPA at alkanolamine dosages of 0.1% and 0.2%. The compressive strength and non-evaporable water content were enhanced by the four types of alkanolamines (dosage of 0.03%) at 3 d, 7 d and 28 d, which allowed TEA and DEIPA to contribute to strength development and the hydration reaction over TIPA and MDEA. The CH content, porosity and pore size were decreased by alkanolamines at different ages. Alkanolamines promoted the formation of ettringite and an alumina–ferric oxide–monosulfate phase, and the C–S–H morphology was also changed by different kinds of alkanolamines. [ABSTRACT FROM AUTHOR]

Although the side chain ionizability (the adsorption group density and adsorption space are changed) of polycarboxylate superplasticizer (PCE) serve as the key structural parameter in affecting the cement hydration, its effect on cement hydration is unclear. Based on PCE with nonionizable side chain (NSC-PCE) and the PCE with ionizable side chain (ISC-PCE), the influence of the side chain ionizability of PCE on the hydration behavior of cement was studied. Compared with NSC-PCE, ISC-PCE has a stronger ability to change the migration of water and ions, thus delaying the crystal nucleation and growth of cement hydration (better morphology and distribution, the crystal size was reduced by more than 20 %), increasing the crystal growth index (tendency toward spherical growth), prolonging the phase boundary reaction (reduce micro-cracks), which was conducive to the formation of more uniform and dense crystals (good strength, ISC-PCE: 50.0 MPa > NSC-PCE: 49.2 MPa > Blank: 48.7 MPa). These findings provide the design basis and theoretical guidance for the innovative development of PCE. [Display omitted] • ISC-PCE decreases the hydration rate and hydration degree of cement. • The effect of PCE on the hydration process was studied by the hydration kinetics model. • ISC-PCE has a stronger ability to change the migration of water and ions. • Proposes working mechanism in viewpoints of dissolution-precipitation equilibrium. • Tailoring the side chain ionizability was a new strategy to tune the performance of PCE. [ABSTRACT FROM AUTHOR]

• Effective modification of extruded polystyrene foam (XPSF) by the ultraviolet-ozone. • Amphipathic silane coupling agents as the adhesion promoters between XPSF and mortar. • A significant improvement on the interfacial strength of XPSF/mortar. • The chemical linkages can be induced by different kinds of silanes. The inert surface of extruded polystyrene foam (XPSF) was activated by the ultraviolet-ozone (UVO) irradiation, followed by the surface coupling reactions with γ-mercaptopropyl trimethoxysilane (MPTMS) and vinyl triethylsilane (VTEO) to improve the interfacial affinity between the organic XPSF and inorganic mortar. The reaction conditions (including reaction time, concentration and pH of the silanes) were thoroughly investigated in order to reach the maximum bonding strength (BS) of XPSF/mortar composites. It was suggested that the presence of MPTMS could increase the BS value from 0.04 MPa to 0.178 MPa (reaction time: 10 min, concentration of MPTMS: 2% and pH value of the silane solution: 4). For VTEO, the maximum BS value reached to 0.140 MPa (activation and reaction time: 7 and 3 min, concentration of VTEO: 5% and pH value of the silane solution: 7). According to the mechanism analysis, the thiol groups in MPTMS have the strongest reactivity with activated XPSF surface after UVO exposure, leading to the maximized interfacial strength between the organic insulation materials and inorganic mortar. [ABSTRACT FROM AUTHOR]

Abstract: To make clear the environmental damages and potential improvements of Chinese cement industry, the detailed life cycle inventory (LCI) of cement manufacture with direct input and output in the boundary of cement plant as well as corresponded transport is conducted. The functional units are 1 t of Portland Ordinary cement and 1 t of clinker. The input data contain not only the traditional items such as raw materials (limestone, sandstone, ferrous tailings and gypsums), energy (coal and electricity), and admixtures (fly ash and furnace slag), but also fresh water which is not paid attention in other literature. The output data contain not only greenhouse gas (CO2) and primary pollution (NO x , PM, SO2), but also the hazardous air pollutants (HCl, NMVOC, PCDD/Fs, PAHs and fluoride) as well as noise and heavy metal emissions (As, Cd, Cr, Hg, Ni, Pb, Zn, Cu) which are usually neglected by others. The data were measured on-site. The applications of reducing pollutants and waste heat recovery technologies, and AFRs usage in cement industry are evaluated. The three steps of developments of LCI study for China cement industry are discussed. [Copyright &y& Elsevier]

This study fabricated a kind of novel phase change microcapsules with a metal-polymer hybrid capsule shell for applying in gypsum materials to reduce building energy consumption. The microstructure, composition and thermal characteristics of the microcapsules were investigated by using techniques such as the scanning electron microscope, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and differential scanning calorimetry. Their impact on the thermal regulation characteristics of gypsum composite materials was also analyzed through the heating plate test and simulated room experiment. Results show the microcapsules with inner organic polymer and outer copper layer were successfully fabricated. And they exhibited a phase change temperature between 22.3 ℃ and 23.3 ℃ and latent heat between 82.2 J/g to 139.5 J/g. Meanwhile, the thermal inertia and thermal storage capacity of gypsum composites were enhanced by incorporating the final microcapsules. After heated for 40 min, the gypsum composite board with MPCM-Cu shows the ability to reduce the room temperature fluctuation. Furthermore, the thermal performance of MPCM-Cu remains stable after 250 thermal cycles. These results indicate that final microcapsules exhibit the potential for building energy conservation. [Display omitted] • MPCM-Cu with binary esters as core and polyurea-copper hybrid shell are synthesised. • The phase change temperature of MPCM-Cu is within the human comfort temperature range. • Higher MPCM-Cu content results in lower temperature fluctuation of gypsum composite. [ABSTRACT FROM AUTHOR]

In this study, the impacts of CO 2 -absorbed triethanolamine solutions (TEA-CO 2) on the mechanical property, phase composition and micro-structure of cement mortars were investigated. The results showed that TEA-CO 2 addition increased the 1d, 3d, and 28d compressive strength by 47%, 19%, and 4%, respectively, which suggests a synergistic effect of triethanolamine and absorbed CO 2 on strength development of cement mortars. The enhancement is due to TEA-CO 2 accelerates hydration of aluminate and silicate phases in early age. TEA-CO 2 facilitated CaCO 3 formation to increase cement hydration degree and modify the pore structures. However, the hydration of silicate phases was delayed slightly by TEA-CO 2 at 28d. The above results provide theoretical support for further utilization of CO 2 in cementitious materials. • Effect of TEA-CO 2 on strength development of mortars was investigated. • TEA-CO 2 addition increases flexural and compressive strength of mortars. • TEA-CO 2 accelerates the hydration of aluminate phase and silicate phase at early age. • A synergism of cement hydration and carbonation in the presence of TEA-CO 2 was proposed. [ABSTRACT FROM AUTHOR]

UV curable organic-inorganic hybrid (OIH) coatings were used to modify the extruded polystyrene foam (XPSF) surfaces to increase the bonding strengthen (BS) of XPSF/mortar composite (XMC). OIH coatings contained polyurethane acrylate, hexanediol and nanoparticles with different dimensions. With the addition of nano-SiO 2 and halloysite nanotubes, the BS-D (BS in dry state) & BS-W-2H/7D (BS in wet state after 2-hour/7-day drying) values for modified XMC were increased from 0.050 & 0.039/0.047 MPa to 0.245 & 0.196/0.356 and 0.312 & 0.233/0.323 MPa. The chemical bonding between SiO 2 /-COOH from UV coating and hydration products in mortar improved the bonding state. [Display omitted] • Modification of XPSF surface by UV curable organic-inorganic hybrid coating. • The fabrication of chemical bonding for XPSF/mortar interfaces. • The investigation of the reactions between mortar and modified XPSF surface. [ABSTRACT FROM AUTHOR]

• The hydration of glass is heterogeneous due to phase-separation structure; • The heterogeneous hydration of glass impact the formation of calcium hydroxide; • The hydration rate advantage of calcium-rich and silicon-rich phase can be reversed; • The heterogeneous hydration is suitable for thermodynamic simulation of cement paste; Supplementary cementitious materials (SCMs) affect the hydration process and long-term properties of cementitious systems. Since a large percentage of SCMs belong to alkaline-earth aluminosilicate glasses that possess a phase-separated structure, further research into their hydration characteristics is essential. This study investigated the effects of the hydration characteristics of synthetic glasses with various phase-separated structure on the phase evolution of cementitious systems by combining simulations with experiments. The results showed that with the increasing degree of phase separation, the hydration of synthetic glass transitions from homogeneous to heterogeneous hydration. The phase evolution of hardened paste, particularly for calcium hydroxide, is influenced by the difference in hydration rates among each separated glassy phase. Compared to homogeneous hydration, the rapid hydration of the Ca-rich phase reduced the consumption of calcium hydroxide, while the rapid hydration of the Si-rich phase accelerated calcium hydroxide consumption. For glasses exhibiting phase separation characteristics, the consistency between thermodynamic simulations employing a heterogeneous hydration model and experimental results exhibits a notable enhancement. [ABSTRACT FROM AUTHOR]

In this paper, star -like polycarboxylate superplasticizer (SPCE) and comb -like polycarboxylate superplasticizer (CPCE) were prepared via atom transfer radical polymerization (ATRP) to study the mechanism of the effectiveness enhancement resulting from this transformation of topological structure. It was found that SPCE molecules acted higher adsorption amount and more Ca2+ complexes, and formed a lower and more compact adsorbed layer and larger surface coverage with a flat conformation on cement surface, depending on more anchored points per unit volume. Through this mechanism, cement particles adsorbed by SPCE showed stronger dispersible capability and colloidal interaction forces (the steric force was dominant), resulting in lower yield stress and plastic viscosity of the cement paste containing SPCE which behaved as an ideal Bingham fluid. The aim of this study is to clarify the mechanistic correlation between topological structure evolution and effectiveness promotion for PCE. [Display omitted] • Topological transformation of PCE helps to enhance effectiveness via more adsorbed points per unit volume. • SPCE molecules adsorb as a flat conformation to present a low and compact layer on cement surface. • Rheological properties of cement pastes depend on the interparticle steric force which plays a dominant role. • Good agreement is shown among the measured adsorbed layer thickness, R h value and surface coverage. • Novelty changing to dense topological structure is proved as a promising way to obtain highly effective PCE. [ABSTRACT FROM AUTHOR]

• New sights on NO reduction with biomass char using Raman/XPS/XRD analysis. • Significant changes in char structures were found during the heat treatment/gasification. • Char-NO reaction and char-O 2 reaction preferentially happened following different pathways. • Relations between structural evolutions of chars and their denitration abilities were explored. NO reduction with biomass char was studied from considering its structural properties. Raman, XPS and XRD were employed to characterize the char structure. Three types of biomass chars were used for NO reduction at a fixed bed reactor in NO/O 2 at 900 ℃. The results showed that the heat treatment led to an obvious reordering of structures in all chars. There were significant differences between NO and O 2 reaction in terms of the char structural changes in aromatic systems, surface groups and crystalline developments. New O-containing groups were formed and could be present as C-O and –COO groups in both the NO and O 2 reactions. Two different pathways for char-NO and char-O 2 reaction were given, respectively. It is proposed that the reaction channel of NO would be blocked as carbon molecular was firstly surrounded by O 2 during NO/O 2 reaction. The denitration performance of biomass char should be linked to the structural features of char-HT and the behaviors of char structural changes in the subsequent gasification in NO/O 2. [ABSTRACT FROM AUTHOR]

China was positioned as the world's largest producer and consumer of ceramic tiles, accounting for 50% of tile production and 40% of tile consumption in the world approximately. Recently, Chinese ceramic industry has increased its focus on environmental issues with the aim of protecting natural resources and reducing pollutant emission. This study evaluated and compared the environmental impacts of ceramic tiles produced by traditional technology and cleaner production technology using life cycle assessment methodology with "cradle to gate" perspective. The results showed that the energy consumptions and emissions from fuel combustion were the hotspots of the environmental impact caused by tile production. The drying and firing processes were the main contributors to the energy consumption at the ceramic production stage. Moreover, the environmental impact reduction potential of different cleaner production technologies was elaborated in this paper. The results proved that applying natural gas as fuel instead of coal (producer gas) caused less damage on human health and ecosystem but more damage on the resource. The dry-milling process has potential to reduce environmental impacts compared with wet-milling process in all midpoint and endpoint indicators. In addition, the sensitivity analysis of input parameters, transportation distance and qualified products rate was conducted to identify the key parameters that have great influence on the results. • Ceramic products from four typical plants in China was analyzed using LCA. • Environmental impact of different fuel scenarios and milling technologies was compared. • Applying the natural gas as fuel instead of coal (producer gas) caused less damage on human health and ecosystem. • Dry-milling process have potential to reduce the environmental impact compared with wet-milling process. • Sensitivity analysis related to input parameter, transport distance and qualified products rate were conducted. [ABSTRACT FROM AUTHOR]

• A certain dosage of DEA or TEA helps to increase the application performance of accelerator. • The complexation effect of DEA and TEA in accelerator have a significant difference. • DEA in accelerator promote the C 3 S hydration in the initial stage of hydration. • High dosage of TEA in accelerator increases the formation rate of AFt and inhibit the hydration of C 3 A and C 3 S. • Transformation of DEA-Al to DEA-Ca occurred in the cement hydration when accelerator containing DEA. In this study, diethanolamine (DEA) and triethanolamine (TEA) were used to prepare a series of liquid alkali-free accelerators to investigate the different effects of complexation of DEA and TEA in accelerators towards the initial stage of cement hydration. Two types of accelerators respectively containing DEA (dosages of 0, 6, 8, 10, 12%) and TEA (dosages of 0, 0.25, 0.5, 0.75, 1, 8%) were prepared, and after addition, the setting time of cement pastes and compressive strength of mortars were tested. The result showed that the optimum dosage of DEA and TEA in accelerators was 8% and 0.25% respectively, and the early-strength effect of TEA was stronger than that of DEA. The mechanisms of DEA and TEA in accelerators were further revealed in terms of complexation capacity, concentration of Ca2+, and hydration products and microstructure morphology of cement pastes. DEA and TEA complexed with Al3+ in accelerators and promoted the formation of ettringite (AFt) in cement pastes, and the complexation capacity of TEA to Al3+ was stronger than that of DEA, causing that high dosage of TEA in accelerator promoted the formation of AFt more than DEA and covered at the surfaces of C 3 A and C 3 S, which inhibited the hydration. DEA in accelerator could promote the hydration of C 3 S in the initial stage due to the transformation of complex DEA-Al to DEA-Ca. This study aims to interpret the different influences of complexation effects of DEA and TEA in accelerators on the properties of cement-based materials and their working mechanisms. [ABSTRACT FROM AUTHOR]

Chemical admixtures are indispensable functional ingredients in modern construction, and their raw materials for synthesis are mainly sourced from petrochemical products, leading to petrochemical resource consumption and environmental damage. Using biomass as a raw material for preparing chemical admixtures for concrete is an effective and environmentally friendly method that holds great promise for overcoming these environment problems and obtaining exceptional application properties. This work systematically addresses the recent research advances in chemical admixtures using polysaccharide, polyphenol biomass and biorefineries, including their preparation methods, application effects and environmental impact assessment. The results show that the molecular structures of polysaccharide and polyphenol biomass contain a large number of active functional groups, which help bio-based chemical admixtures to be prepared by acylation, sulfonation and/or graft copolymerization, significantly improving the dispersibility, water retention, retardation, anti-adhesion and durability of cement-based materials. Also, the use of biorefinery technology endows chemical admixtures with superior environmental performance. In addition, this review addresses the importance of the life cycle assessment (LCA) method in evaluating the environmental impacts of bio-based chemical admixtures and establishes that environmental pollution can be substantially minimized by optimizing the preparation process (e.g., use of renewable raw materials, adoption of biorefineries, etc.). This article gives an overview on bio-based chemical admixtures and their high-value utilization and ecological development that provide a theoretical basis for the design of energy-saving and low-cost bio-based chemical admixtures. [Display omitted] • Potential application of biomass in preparation of environment-friendly admixtures. • Preparation processes of conventional and new bio-based admixtures were compared. • Bio-based admixtures show better properties and lower environmental impact. • Application of LCA methodology in preparation of bio-based chemical admixtures. • Performance and environmental benefits of biomass into bio-based admixtures. [ABSTRACT FROM AUTHOR]

Effects of disodium EDTA (EDTA-2Na) on hydration and mechanical properties of calcium sulphoaluminate-belite cement (CSBC) were investigated systematically. Results show that EDTA-2Na addition leads to visible changes in CSBC strength development. 0.50 % EDTA-2Na significantly enhances the compressive strength by 18 % and 23 % compared with the blank specimens at 7 d and 28 d, while reducing the strength at 8 h and 1 d. The content of the main hydration product (AFt) determines the strength development. At the early hydration stage, EDTA-2Na delays hydration of ye'elimite to form AFt, thus decreasing the early hydration degree of CSBC and increasing the porosity to reduce strength. In the presence of EDTA-2Na, the morphology changes of amorphous aluminum hydroxide (AH 3) facilitate the AH 3 -C 2 S-CaSO 4 reaction to increase AFt content and form a more condensed structure, thus enhancing the late strength. In this way, the strength development of CSBC mortars can be modified and regulated by EDTA-2Na. [ABSTRACT FROM AUTHOR]