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In this work, we study a geometric structure called disjoint convex shell or simply DC-shell. A DC-shell of a polyhedron is a set of pairwise interior disjoint convex objects that collectively approximate the given polyhedron. Preventing convex objects from overlapping enables faster and robust collision response and more realistic fracturing simulation. Without the disjointness constraint, a physical realization of the approximation becomes impossible. This paper investigates multiple approaches that construct DC-shells from shapes that are either composed of overlapping components or segmented into parts. We show theoretically that, even under this rather simplified setting, constructing DC-shell is difficult. To demonstrate the power of DC-shell, we studied how DC-shell can be used in mesh unfolding, an important computational method in manufacturing 3D shape from the 2D material. Approximating a given polyhedron model by DC-shells provides two major benefits. First, they are much easier to unfold using the existing unfolding methods. Second, they can be folded easily by both human folder or self-folding machines. Consequently, DC-shell makes paper craft creation and design more accessible to younger children and provides chances to enrich their education experiences. [ABSTRACT FROM AUTHOR]

Decomposing a 3D model into approximately convex components has gained more attention recently due to its ability to efficiently generate small decompositions with controllable concavity bounds. However, current methods are computationally expensive and require many user parameters. These parameters are usually unintuitive thus adding unnecessary obstacles in processing a large number of meshes with various types and shapes or meshes that are generated online within applications such as video games. In this paper, we investigate an approach that decomposes a mesh P based on the identification of convex ridges . Intuitively, convex ridges are the protruding parts of the mesh P . Our method, called CoRiSe , extracts nearly convex components of P by separating each convex ridge from all the other convex ridges through the new concept of residual concavity . CoRiSe takes a single user parameter: concavity tolerance which controls the maximum concavity of the final components, as input, along with other two fixed parameters for encoding the smoothness term of graph cut. We show that our method can generate comparable (sometimes noticeably better) segmentations in significant shorter time than the current state-of-art methods. Finally, we demonstrate applications of CoRiSe , including physically-based simulation, cage generation, model repair and mesh unfolding. [ABSTRACT FROM AUTHOR]

Three series of co-graft cationic starch (St)-based flocculants with distinct structural characteristics, namely, charge density (CD), graft-chain length (L), and graft-chain distribution (N), were successfully synthesized through graft copolymerization of [(2-methacryloyloxyethyl) trimethyl ammonium chloride] and acrylamide. These St-based flocculants with different molecular structures were used to flocculate various kaolin suspensions with different initial turbidities and a sodium humate (NaHA) aqueous solution. The experimental results indicated that CD contributed to flocculation evidently, whereas average L and its N were insignificant in experimentally measured ranges. On the basis of phenomenological theory, a second-order polynomial equation was used to further quantitatively analyze the effects of the three structural factors on the flocculation performance of these St-based flocculants, which were fully consistent with the experimental results. Besides, the optimal dose and its corresponding removal rate could be predicted exactly, and the flocculation mechanisms were discussed in detail according to the established models. With the combination of floc properties and zeta potentials, the flocculation mechanisms of these St-based flocculants for flocculation of kaolin suspensions and NaHA aqueous solution were mainly ascribed to charge patching and simple charge neutralization, respectively. These results improve the understanding of the structure–activity relationship of these graft St-based flocculants, which is of significant guidance for the utilization and design of novel flocculants. Image 1 • Three series of starch-based flocculants with various molecular structure was prepared. • Charge density contributed evidently to flocculation. • Average graft-chain length and its distributions contributed insignificantly. • The structure–activity relationship was established using a quantitative equation. • Flocculation mechanisms were thus discussed deeply based on the established model. [ABSTRACT FROM AUTHOR]

Highlights • Sasobit modified epoxy asphalt rubber (EAR) has been developed. • The addition of Sasobit lowers the viscosity and glass transition temperature of the neat EAR. • The inclusion of Sasobit increases the number of spherical AR particles in the continuous epoxy phase. • The mechanical properties of the neat EAR are enhanced with the addition 1 wt% Sasobit. Abstract The utilization of crumb rubber to produce asphalt rubber (AR) for asphalt mixture pavement has been proven to be an economical and environmental way for the disposal of waste tires. As one of the most significant thermosetting polymer modified asphalt with prominent performances, epoxy asphalt (EA) has been widely used on the pavement of steel bridge decks. In present study, the mixture of epoxy oligomer and curing agent was incorporated into AR to prepare epoxy asphalt rubber (EAR). To lower the viscosity of AR, a WMA additive, Sasobit was introduced into AR to prepare Sasobit modified EARs. The effects of Sasobit on the rotational viscosity, glass transition temperature (T g), damping performance, mechanical properties and phase-separated morphology of the neat EAR were investigated. The inclusion of Sasobit significantly decreased the viscosity of the neat EAR during the whole curing process and prolonged the operational lifetime for asphalt mixture pavement. The addition of Sasobit slightly decreased the T g of the neat EAR. The T g of Sasobit modified EARs decreased with WMA additive content increasing. Meanwhile, the presence of Sasobit improved the damping properties of the neat EAR. The existence of Sasobit enhanced the mechanical properties of the neat EAR at lower WMA additive concentration. The mechanical properties of Sasobit modified EARs decreased with increasing WMA additive content. Morphological observations revealed that the phase-separated microstructures of the neat EAR consisted of the dispersed spherical and co-continuous AR particles and the continuous epoxy phase. The existence of Sasobit decreased the number of co-continuous AR particles in the epoxy matrix. In addition, the number of co-continuous AR particles decreased with increasing WMA additive content. The presence of Sasobit decreased the average diameter of the dispersed AR particles and area fraction of AR domains in the neat EAR. [ABSTRACT FROM AUTHOR]

Highlights • Halogen-free flame retarded cold-mix epoxy asphalt binder (CEAB) has been developed. • The flame retardancy of the neat CEAB is significantly increased by halogen-free flame retardant. • The addition of halogen-free flame retardants improves the glass transition temperature, thermal stability and tensile strength of the neat CEAB. Abstract Fire safety of asphalt mixtures in highway tunnels has become a problem of great concerns since asphalt and polymer modified asphalt binders are quite flammable and tend to release poisonous gases and smoke while burning. Therefore, flame retardants are incorporated into asphalt binder to improve the fire retardancy of asphalt mixtures. In this paper, aluminum trihydroxide (ATH) and zinc borate (ZB) were used as halogen-free flame retardants to prepare flame retarded cold-mix epoxy asphalt binders (CEABs). The addition of halogen-free flame retardants increased flame retardancy of the neat CEAB. In addition, ATH-ZB retarded CEAB had higher limited oxygen index (LOI) than single ATH and ZB retarded CEABs at the same content. The presence of halogen-free flame retardants increased the viscosity of the neat CEAB. The viscosity of ATH/ZB retarded CEAB was lower than that of ATH retarded CEAB at a specific content. The incorporation of halogen-free flame retardants enhanced the glass transition temperature of the neat CEAB. Thermal stability of the neat CEAB was improved by the halogen-free flame retardants. ATH/ZB retarded CEAB had better thermal stability than ATH retarded CEAB at the same content. The addition of halogen-free flame retardants increased the tensile strength of the neat CEAB. Uniform dispersion of halogen-free flame retardants in CEABs was observed. [ABSTRACT FROM AUTHOR]

Epoxy asphalt adhesive (EAA) has been widely used as strong waterproof-bonding layers for the orthotropic steel bridge decks in China. This research employs attapulgite (ATT), one kind of natural fibrous nanoclays, as the nanofiller to reinforce EAA. The crystalline structure, rheological property, thermal stability, mechanical properties and morphology of EAA/ATT composites were investigated by X-ray diffraction (XRD), Brookfield rotational viscometer, thermogravimetric analyzer (TGA), universal test machine and scanning electron microscopy (SEM). Results showed the existence of ATT did not change the noncrystalline structure of the EAA. ATT had a significant decrement effect on the rotational viscosity of EAA. Moreover, the viscosity of EAA/ATT composites decreased with the increasing content of ATT at a specific cure time. The addition of ATT improved thermal stability of the neat EAA. In addition, the incorporation of ATT increased the tensile and adhesive properties of the neat EAA. The tensile strength, toughness, Young's modulus and adhesive strength of EAA/ATT composites increased with the increase of ATT loadings. [ABSTRACT FROM AUTHOR]

[Display omitted] • Core-shell rubbers (CSRs) with two core polymers have been used to toughen epoxy asphalt (EA). • 2 wt% CSR with polybutadiene (PB) core alters the phase separation mechanism of EA. • Both swollen polymer and asphalt particles form in the continuous epoxy phase of EA. • The area fraction of swollen PB particles is higher that of swollen SB particles. • EA modified by CSR with PB core exhibits higher damping and mechanical properties. Core-shell rubber (CSR) is a good candidate for toughening epoxy asphalt binders. However, the knowledge of the effect of the core polymer on the performance of CSR modified hot-mix epoxy asphalt binder (HEAB) is not completed and systematic yet. In this paper, CSR modified HEABs were prepared by the incorporation of 2 wt% CSR particles with different core polymers, which were in turn subjected to viscous measurements, confocal microscopy, thermogravimetric analysis, dynamic mechanical analysis and tensile tests. The results revealed that the viscosity of CSR with styrene-butadiene copolymer (SB) core (CSR SB) modified HEAB is higher than that of CSR with polybutadiene (PB) core (CSR PB) modified HEAB during curing. The shell destruction of CSR particles resulted in the swelling of the core polymers and dispersion of swollen core polymer particles in the epoxy phase in the micron scale along with asphalt particles. The phase separation of CSR PB modified HEAB occurred in the spinodal decomposition mode, which was different from the nucleation and growth mechanism of the neat and CSR SB modified HEABs. The area fraction of swollen PB particles in the CSR modified HEAB was greater than that of swollen SB particles. The core polymer had a negligible effect on the thermal stability of CSR modified HEABs. The glass transition temperatures of epoxy and asphalt, damping ability and mechanical properties of the neat HEAB were increased with the addition of CSR particles. Especially, CSR PB modified HEAB had higher tensile strength and toughness than CSR SB modified HEAB. With 2 wt% CSR PB particles being adding, the tensile strength, elongation at break and toughness of the neat HEAB were increased by 53%, 42% and 110%, respectively. [ABSTRACT FROM AUTHOR]

• Thermal shock significantly increases the pull-off strength of the touch-dry BEBC. • The hydrophilic touch-dry BEBC becomes hydrophobic after the thermal shock. • Thermal shock greatly increases the T g of the touch-dry BEBC. • The touch-dry BEBC's tensile strength increases by about 300% after the thermal shock. • Thermal shock temperature has a limited effect on the mechanical properties of BEBCs. B-staged epoxy bond coat (BEBC) has been widely applied as a waterproof adhesive layer in the pavements of orthotropic steel bridges. During its application, the uncured BEBC layer was first paved on the surface of the steel deck or the bituminous surfacing and hot bituminous mixture would be constructed until the BEBC layer became touch-dry. In this paper, the impacts of thermal shock on the degree of cure (DOC), pull-off strength, hydrophilicity, glass transition temperature (T g), damping performance, thermal stability and mechanical behaviors of the touch-dry BEBC were investigated. Thermal shock greatly increased the DOC of the touch-dry BEBC and the touch-dry BEBC turned to be nearly fully cured after the thermal shock at a higher temperature. The pull-off strength of the touch-dry BEBC was remarkably improved by the thermal shock. After the thermal shock at 160 °C, the pull-off strengths at room temperature and at 60 °C of the touch-dry BEBC were increased by 584% and 914%, respectively. After the thermal shock, the contact angle of the touch-dry BEBC was greatly increased and the hydrophilicity of the touch-dry BEBC was converted to hydrophobicity. Thermal shock significantly increased the T g of the touch-dry BEBC. Furthermore, the T g of thermally shocked BEBCs slightly increased in the temperature. Thermal shock improved the damping performance of the fully cured BEBC. The tensile strength and toughness of the touch-dry BEBC were greatly improved by the thermal shock. However, thermal shock lowered the elongation at break of touch-dry BEBC. In the case of thermally shocked BEBCs, the temperature had a limited effect on the tensile strength, while the elongation at break increased in the temperature. The fracture energy first decreased in the temperature and increased after 150 °C. Maximum fracture energy appeared at 160 °C. After the thermal shock, the tensile strength of the touch-dry BEBC was increased by as much as 3-fold. The fracture energy of the BEBC thermally shocked at 160 °C was 182% greater than that of the touch-dry BEBC. [ABSTRACT FROM AUTHOR]

[Display omitted] • Eco-friendly fire-retarded warm-mix epoxy asphalt binders (WEABs) have been developed. • RPFR of significantly improved the fire retardancy of the pure WEAB. • RPFR hinders WEAB's cure reaction and extends the allowable construction time of WEAB mixtures. • RPFR improves the glass transition temperature and thermal stability of the pure WEAB. • Double phase separation forms in RPFR modified WEABs. Epoxy asphalt binder is flammable and plenty of fumes are produced during its high-temperature pavements in tunnels. To improve fire retardancy and reduce asphalt fumes, eco-friendly flame-retarded warm-mix epoxy asphalt binders (WEABs) for road tunnel pavements were developed by incorporation of reactive polymeric flame retardant (RPFR), which was composed of a reactive polymeric brominated epoxy oligomer (BEO) and antimony oxide. The influence of RPRF on flame retardancy, rotational viscosity, microstructures, thermal properties and mechanical performance of the pure WEAB was investigated using various techniques: oxygen index instrument, Brookfield viscometer, confocal microscope, differential scanning calorimeter, thermogravimetric analyzer and universal testing machine. The presence of RPFR significantly improved the limited oxygen index (LOI) of the pure WEAB. The LOI of RPFR modified WEABs increased in the flame retardant loading. The reaction of epoxide groups of RPFR with the curing agents of epoxy asphalt reduced the viscosity of the pure WEAB and extended the allowable construction time of the WEAB mixture. The inclusion of RPFR increased the glass transition temperature (T g) of the pure WEAB. For modified WEABs, the T g increased in the RPFR loading. RPFR reacted into the epoxy asphalt backbone through the reaction between epoxy groups and curing agents. The incorporation of RPFR improved the thermal stability of the pure WEAB. The addition of 8 wt% RPFR increased the tensile strength of the pure WEAB, while the inclusion of RPFR slightly decreased the break elongation of the pure WEAB. Double phase separation occurred in RPFR modified WEAB: the main phase separation included the continuous epoxy phase and the discontinuous asphalt domains, in which the secondary phase separation formed with asphalt as the continuous phase and spherical BEO domains as the discontinuous phase. The particle size of BEO domains decreased with the increase of the RPFR loading. [ABSTRACT FROM AUTHOR]

• Phase separation of ESBA disrupts the original dispersion of SBS in the asphalt. • The size of SBS domains in ESBAs increases in the SBS loading. • ESBA's viscosity increases in the SBS loading. • The thermal stability of ESBAs enhances with the increase of SBS loading. • The neat EA's elongation at break increases by 56% with the addition of 3 wt% SBS. Both styrene–butadiene-styrene copolymer (SBS) and epoxy resin have been widely applied in the asphalt modification. The influence of SBS concentration on the morphology, viscosity, thermal stability, glass transition temperature (T g), damping performance and mechanical behaviors of the neat EA binder was studied. Double phase separation occurred in the epoxy SBS modified asphalt (ESBA): main phase separation between epoxy and the SBS modified asphalt (SBA) and secondary phase separation between asphalt and SBS. The occurrence of phase separation in the ESBA disrupted the original dispersion of SBS particles in SBA and resulted in the redistribution of SBS in the form of smaller spherical particles. The inclusion of SBS increased the viscosity of the neat EA. Furthermore, the viscosity of ESBAs increased with the SBS content. ESBAs had as long as 150-min construction time for the mixture pavement. The presence of SBS improved the thermostability of the neat EA. In terms of ESBAs, the thermostability increased with the SBS content. The addition of SBS lowered the T g of the neat EA when the SBS content was lower than 4 wt%. The T g of ESBAs increased with the SBS content. The incorporation of SBS significantly enhanced the damping behaviors of the neat EA. The tensile strength of the neat EA was improved with the addition of 2 wt% SBS. The inclusion of SBS improved the elongation at break and the toughness of the neat EA when the SBS loading was greater than 1 wt%. [ABSTRACT FROM AUTHOR]

• A series of actinia-shaped lignin-based adsorbent (LNAEs) was designed and fabricated. • The prepared LNAEs were applied to remove ofloxacin and ciprofloxacin from water. • Electrostatic attraction and hydrogen bonding were mainly involved in this adsorption. • Adsorption mechanisms were revealed from graft-chain length and distribution of LNAEs. • Structure-activity relationship of this adsorbent was built using a simple model. A series of actinia-shaped lignin-based adsorbents (LNAEs) featuring lignin(LN) as the core and grafted poly(acrylic acid) (PAA) as the tentacle were designed and fabricated. LNAEs were applied to remove ofloxacin and ciprofloxacin from water, and their maximum adsorption capacities were 0.835 and 0.965 mmol/g at pH 6.0, respectively. However, their adsorption capacities were up to about 20 % and 31 % reductions in the present of NaCl and humic acid, respectively. Electrostatic attraction (EA) and hydrogen bonding (HB), including ordinary HB and negative charged auxiliary HB, were mainly involved in adsorption. Experimental and calculation results indicated HB contributes more than EA. The effects of two structural factors of LNAEs, namely, PAA branched-chain length(L) and distribution density(D), on the adsorption performance associated with HB and EA, were quantitatively discussed using a binary nonlinear model based on phenomenological theory. The fitting results were completely consistent with the experimental findings. D was more efficient than L in promoting HB and EA in adsorption due to the cooperative effects of adjacent branched-chains and enhanced activity of terminal groups. This study provides a better understanding of the structure–activity relationship of surface grafting-modified adsorbents and fundamental guidance for the exploitation and design of novel and efficient adsorbents. [ABSTRACT FROM AUTHOR]

In this work, a simple and environmentally-friendly enhanced coagulation, by using a cationic starch-based coagulant (starch-3-chloro-2-hydroxypropyl trimethyl ammonium chloride, St-CTA) coupled with an optimized polysilicic acid (PSA), has been tried to coagulate the kaolin suspensions and humic acid (HA) aqueous solutions, which are used as the simulated sources of inorganic colloidal particles and organic pollutant, respectively, in micro-polluted turbid surface water. Dosing of St-CTA and PSA at the same time is more efficient and more convenient than other two separated feeding methods in this enhanced coagulation process. The synergic coagulation process and mechanism were studied and discussed in detail based on the apparent coagulation performance, floc properties, and zeta potentials of supernatants. St-CTA caused an efficient charge neutralization, i.e. compression of electric double layer of kaolin particles and electrostatic adsorption of HA, followed by an effective netting-bridging effect of PSA, resulting in an improved purification performance. St-CTA with a higher charge density showed better purification performance due to enhanced charge neutralization effect. In addition to simulated water, the validation of this enhanced coagulation process was further confirmed by comparison with a conventional coagulant, polyaluminium chloride, in treating a real surface water. This work thus provides a simple and environmentally-friendly strategy to efficiently purify micro-polluted turbid surface water and further improve the water safety. Image 1 • An enhanced coagulation is provided by a cationic starch aided with polysilicic acid. • This strategy effectively purifies the micro-polluted turbid surface water. • Two agents dosed together show highly efficient purification performance. • Charge neutralization and netting-bridging effects play important roles. • The validation of this enhanced coagulation is confirmed by treating a real water. [ABSTRACT FROM AUTHOR]

• Core-shell rubber (CSR) nanoparticle toughened epoxy asphalt (EA) has been developed. • The toughness of the pure EA increases by 2-fold with only addition of 1 wt% CSR. • The shell of CSR is broken and the core of CSR swells in the EA. • Newly micro-scale CSR phase uniformly disperses in the epoxy phase of the EA. • CSR nanoparticles alters the mechanism of phase separation of the pure EA. Core-shell rubber (CSR) has been widely applied in the improvement of the toughness for the brittle epoxy resin. In this study, an epoxy asphalt (EA) binder has been toughened by the inclusion of CSR nanoparticles with approximately 100–200 nm in diameter. The incorporation of CSR nanoparticles significantly increased the viscosity of the pure EA during curing. Even with 5 wt% CSR, the EA blend exhibited extremely long operational lifetime (more than 2.5 h) for mixture pavements. The glassy shell of CSR nanoparticles was broken and the rubbery core of CSR nanoparticles swelled in the EA. New micro-scale CSR domains formed and uniformly dispersed in the epoxy phase of the cured EA. The inclusion of CSR nanoparticles altered the phase separation mechanism of the pure EA. The sea-island morphology of the pure EA took place through the nucleation and growth (NG) mechanism, while co-continuous microstructures in the EA blends with 3 wt% and 5 wt% CSR formed through the spinodal decomposition (SD) mechanism. Both sea-island and co-continuous microstructures via combined the NG and SD mechanisms were observed in the EA blend containing 1 wt% CSR. The glass transition temperature and thermal stability of the pure EA was improved by the inclusion of higher CSR loadings. The incorporation of CSR greatly enhanced the mechanical properties of the pure EA. In the case of 1 wt% CSR inclusion, 29% increase in the tensile strength, 60% improvement in the elongation at break and 2-fold increment in the toughness were obtained. [ABSTRACT FROM AUTHOR]

• Waste cooking oil (WCO) modified epoxy asphalt binder (EAB) has been developed. • WCO lowers the viscosity and thus extends the construction time of the neat EAB. • Phase inversion in WEAB occurs when 6 wt% WCO is added. • WCO improves the low-temperature performance of the neat EAB. • WCO enhances the damping properties and thermal stability of the neat EAB. Waste cooking oil (WCO) was used as a warm mix asphalt (WMA) additive to modify warm-mix asphalt binder (WEAB) with the expectation of lowering the viscosity and prolonging the construction time of the binder. The viscosity, phase separation, viscoelasticity, thermostability and mechanical properties of WCO modified WEABs were studied and compared with the neat WEAB. WCO significantly reduced the WEAB's viscosity and extended the construction time of the neat WEAB. Moreover, the reducing and prolonging effects increased with the WCO content. Phase-inverted microstructure and secondary phase separation formed in the modified WEAB with 6 wt% WCO. The inclusion of WCO improved the low-temperature performance of the neat WEAB. The damping behavior and thermostability of the neat WEAB were improved with the inclusion of WCO. The presence of WCO increased the elongation at break of the neat WEAB when the waste oil content was lower than 4 wt%. [ABSTRACT FROM AUTHOR]

• Brominated SBS (BrSBS) modified epoxy asphalt (EBrSA) binder has been developed. • The nucleophilic substitution reaction occurs between BrSBS and amine curing agent. • Phase inversion takes place in the EBrSAs with higher BrSBS contents. • The flame retardancy of the neat HEAB is significantly improved by BrSBS. • BrSBS greatly increases the glass transition temperature of the neat HEAB. Brominated styrene–butadienestyrene triblock copolymer (BrSBS) is a novel polymeric flame retardant (PolyFR), which is eco-friendly due to its huge molecule weight. In this paper, BrSBS was added into an epoxy asphalt binder (EAB) to enhance the flame resistance of EAB. The microstructure, viscosity, fire resistance, thermal stability, dynamic mechanical behaviors and mechanical properties of BrSBS modified EABs (EBrSAs) were studied. Double phase separation occurred in EBrSAs. BrSBS modified asphalt (BrSA)-rich phase co-continuously dispersed in the continuous epoxy matrix when BrSBS content was lower. However, phase-inverted morphology appeared when the BrSBS content was higher. In other words, the epoxy-rich phase dispersed in the continuous BrSA-rich phase. The amine curing agent reacted with BrSBS through a bimolecular nucleophilic substitution (S N 2) mechanism, resulting in the formation of epoxy/BrSBS interpenetrating polymer networks (IPNs). The incorporation of BrSBS greatly increased the viscosity of the neat EAB due to the nucleophilic substitution reaction between BrSBS and amine curing agent. BrSBS with lower loading significantly improved the flame retardancy of the neat EAB. BrSBS lowered the thermal stability, mechanical and damping behaviors of the neat EAB. However, the glass transition temperature (T g) of the neat EAB was notably enhanced with the inclusion of BrSBS. [ABSTRACT FROM AUTHOR]