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external energy input (e.g., electricity, heat, light, and humidity) into mechanical work to realize versatile and complex motions, allowing for a range of applications including soft robotics, artificial muscles, medical applications, and sensors. [2] In this context, photoactuators are particularly attractive because light can provide remote and noncontact energy supply and spatiotemporal control over the actuation. [3] Recently, a number of materials based on liquid-crystalline polymers, hydrogels, and photoswitchable moieties-bearing polymers that can undergo large deformation and reversible shape change arising from photochemical or photothermal effect have been designed and utilized to fabricate photoactuators. [4] Among them, the actuators using near-infrared (NIR) light as a actuation source seem more promising especially for biological applications owing to the deeper light penetration through tissues and less damage to biomaterials, as compared to UV and visible (Vis) light. [5] Thus far, studies of soft photoactuators have mainly focused on liquid crystal elastomers (LCEs) and networks (LCNs). [6] Two approaches are usually utilized to fabricate such actuators by either mixing photothermal conversion agents (e.g., carbon nanotube, graphene, metal nanomaterials, and organic compounds or materials) with LCEs or incorporation of organic dyes into polymer chains. [7] As such, the photothermal-induced LC-isotropic phase transition can be achieved and consequently impart the actuators with diverse intriguing motions such as bending, twisting, oscillations, and crawling. [7c,8] In order to realize complex shape deformation and multifunctionality of the actuators, controlling the spatial configuration of the LCNs in the directionality and hierarchical orientation is usually needed. [9] Some systems successfully achieve complex shape morphing by a single-layer LCN film with special LC orientation controlling, and in some cases, bi-and multi-layer systems comprised of a responsive LCN and a passive material layer are employed for this purpose. [8c,10] It is noted that constructing a single-layer, single-component actuator with complex shape deformations is highly desirable, thus increasing their versatility and the range of applications. [11] Semicrystalline polymers (SCPs) represent an important class of shape memory polymers (SMPs). Because of the ease Light-driven soft actuators with adaptive shape changes, diverse geometric morphing, and reversible macroscopic movements have gained everincreasing interest owing to their diverse applications ranging from biomedical to aerospace devices. Herein, presented is a near-infrared (NIR) light-stimulated actuator based on cis-1,4 polybutadiene-polyethylene semicrystalline copolymer. In the system, a newly synthesized croconaine dye, 2,5-bis[(6-(11-carboxyundecanoate)hexyl-4-carboxylate-piperidylamino) thiophenyl]-croconium, serves as both an NIR absorbing agent and crosslinker. Taking advantage of easy processability, two-way shape memory, and photothermal eff...

In this study, we fabricated a porous calcium alginate/graphene oxide composite aerogel by using polystyrene colloidal particles as sacrificial template and graphene oxide as a reinforcing filler. Owing to the excellent metal chelation ability of calcium alginate and controlled nanosized pore structure, the as-prepared calcium alginate/graphene oxide composite aerogel (mp-CA/GO) can reach the adsorption equilibrium in 40 min, and the maximum adsorption capacity for Pb2+, Cu2+ and Cd2+ is 368.2, 98.1 and 183.6 mg/g, respectively. This is higher than most of the reported heavy metal ion sorbents. Moreover, the mp-CA/GO can be regenerated through simple acid-washing and be used repeatedly with little loss in performance. The adsorption mechanism analysis indicates that the mp-CA/GO adsorb the heavy metal ions mainly through the ion exchange and chemical coordination effects.

A polymer network based on a cis-1,4-polybutadiene–polyethylene copolymer exhibits multi- and two-way shape memory effects as well as a high-strain capacity.

Plastic waste gasification is one of the most promising techniques to use nondecomposable solid waste and to produce syngas. A CFD-based Equivalent Reactor Network (ERN) model was developed for simulation of polyethylene gasification in a designed pilot-scale conical spouted bed gasifier. The CFD-based ERN model was established through two steps: (i) hydrodynamics simulations with CFD software and (ii) the equivalent reactor network built in the Aspen Plus simulator with gasification reactions taken into account through external FORTRAN modules. The model predictions were in very good agreement with experimental data of a lab-scale conical spouted bed gasifier used for steam gasification of polyethylene. The developed CFD-based ERN model was then used to investigate the effect of gasification temperature and equivalence ratio on the gasification performance of polyethylene in such a pilot-scale conical spouted bed reactor. It was found that the proper values of temperature and ER for air gasification were 700°C and 0.4, respectively. With this operation condition, a value of LHV of 6.2MJ/Nm 3 , a value of CGE of 72.14%, and a value of CCE of 97.3% were recorded. The present work demonstrated the capabilities of the developed CFD-based ERN model in simulating polyethylene waste gasification process as well as the appropriateness of the designed pilot-scale conical spouted bed gasifier to carry out such a process.

Axial and equatorial bulkiness in the α-diimine Ni/Pd type complexes are two crucial parameters that governs the catalytic activity, thermostability of the precatalysts and molecular weight as well as chain...

investigation of hydrodynamics, heat transfer and cracking reactions in a large-scale fluidized catalytic cracking riser, Applied Mathematical Modelling (2016), 1 Highlights  Hydrodynamics coupled with cracking reactions in an FCC riser were studied. Two-fluid mathematical approach was used to model the fluid-particle flow. Intricate phenomena near a series of injecting nozzles were revealed in detail. A recommendation of an appropriate increasing of the feed injection angle was proposed. Yields and reaction rates of main products and catalyst activity were investigated. ABSTRACTA three-dimensional reactive gas-particle CFD model was built to study the hydrodynamics, heat transfer and cracking reaction behaviors within an industrial Fluid Catalytic Cracking (FCC) riser reactor designed to maximize propylene production. The two-fluid methodology (TFM) was used to simulate the riser hydrodynamics with solid phase properties derived from the kinetic theory of granular flows (KTGF). An 11-lump kinetic model was selected to represent the cracking reaction network in the CFD model. The selection of the kinetic model is dictated by the properties of the feedstock processed and the aim of the process which is maximizing propylene. A novel treatment of the coke component was conducted by incorporating coke into the secondary granular phase which is more realistic since carbon deposition occurs on catalyst phase. Momentum transfer, heat transfer and reaction behavior inside the riser were discussed in detail and inhomogeneity in these aspects were observed especially above the high speed injection nozzles. The numerical results of this investigation show a good agreement with the process real data on the yield distribution despite the use of a coarse grid to mesh such an industrial scale FCC riser. The methodology employed used and the results obtained should serve as guidelines for possible process redesign and optimization.