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Crystallographic analyses of the haloalkane dehalogenase, from Sphingomonas paucimobilis UT26 (LinB), reveal a catalytic triad at the active site. The triad is composed of Asp108, His272, Glu132. The cap domain alpha-helices' composition determines the size and shape of the active-site cavity and its entrance tunnel.

In this work, a waterproof and breathable nanofibrous membrane with thermal‐regulated performance and exhibits excellent mechanical property is fabricated by coaxial electrospinning. The fiber shell is consisted of polyvinylidene fluoride (PVDF) and polyvinyl butyral (PVB), and the core is octadecane. First, well‐performed waterproof and breathable membranes are obtained by optimizing its morphology and pore structure. Then octadecane is loaded into the fibers in the form of core by coaxial electrospinning, though it gives the membranes a thermal regulating function, but the drawback is the sacrifice of overall properties. Thus, carbon nanotubes are loaded into the shell and studied, finally, the best membrane has a comprehensive performance with hydrostatic pressure of 59.2 kPa, water vapor transmission rate (WVTR) of 7.846 kg m−2 d−1, latent heat of 50.1 J g−1, as well as excellent tensile strength of 20.2 MPa, which shows its certain reference significance to the synthesis of multifunctional membrane. [ABSTRACT FROM AUTHOR]

A novel method for fabricating thermo-regulating alginate fiber by wet spinning from phase change material (PCM) microemulsions was proposed and carried out. In order to synthesize the PCM microemulsion successfully, different emulsifiers (alkylphenol polyoxyethylene ether (OP-10), sodium dodecyl sulfate (SDS) and their mixture) were added into the stock solution system. The solution systems with emulsifiers were observed under optical microscope and evaluated by using a differential scanning calorimeter (DSC); the results showed that only the solution system with the mixture of OP-10 and SDS transformed into PCM microemulsion, corresponding to the success of fiber formation by wet spinning. In addition, the microemulsion had a stable thermal property based on the DSC result, in which the latent heat capacity remained at 97.3% after 100 cycles of heating and cooling. The thermo-regulating alginate fiber was evaluated in terms of morphology, thermogravimetric (TG) analysis and differential scanning calorimetry. The results showed that the fiber had a smooth surface and porous structure in the cross-section, the bimodal TG curve of alginate fiber indicated that the PCM was successfully embedded into fiber and the DSC results demonstrated that the thermo-regulating alginate fiber had a comfortable phase change temperature of 25–35℃, and an acceptable phase change enthalpy of about 20 J/g. [ABSTRACT FROM AUTHOR]

Two types of microencapsulated phase change materials (ENPCMs) were synthesized by polymerization. The core material of ENPCM was n -octadecane and the shell materials were polymethyl methacrylate-butyl acrylate and polymethyl methacrylate-butyl acrylate-hydroxyethyl methacrylate. Subsequently, the synthesized ENPCMs were applied onto bamboo fabric by the dip and dry method. The properties of ENPCMs were analyzed in terms of surface morphology, size distribution and latent heat; the treated bamboo fabrics were evaluated in terms of surface morphology, hydrophilicity, washing fastness and heat storage capacity. The results showed that polymethyl methacrylate-butyl acrylate/ n -octadecane (PMBO) microcapsules had an irregular shape, while polymethyl methacrylate-butyl acrylate-hydroxyethyl methacrylate/ n -octadecane (PMBHO) microcapsules were spherical, and the mean diameters of both microcapsules were less than 1 µm. The latent heat of phase change material (PCM) microcapsules was almost the same at a thermal storage capacity of 110 J/g. There were many more and more even PMBHO microcapsules deposited on bamboo fabric than that of PMBO microcapsules deposited on bamboo fabric. Bamboo fabrics treated by both microcapsules were hydrophilic, and the hydrophilicity of fabric treated by PMBHO microcapsules was even better. The ratio of PCM microcapsules to bamboo fabric was about 1:4, and the latent heat of treated bamboo fabrics was about 20 J/g. Moreover, the treated bamboo fabrics exhibited excellent washing fastness due to the strong binding strength between the highly hydrophilic microcapsules and bamboo fibers. Approximately 72% of PCM microcapsules were retained on the fabric after 15 washing cycles. [ABSTRACT FROM AUTHOR]

Activated carbon web is prepared by controlled pyrolysis of acrylic fibrous waste under the layer of charcoal using physical activation in high-temperature furnace. The carbonization was carried out at 1200 °C under different heating rate (i.e. 150 to 450 °C h-1) with different holding time (i.e. 0 to 60 min) to decide optimum pyrolysis parameters. The heating rate of 300 °C h-1 with no holding time revealed higher specific surface area of 280 m2 g-1. The prepared activated carbon web was later employed as adsorbent for removal of methylene blue from aqueous media. The effect of initial dye concentration, adsorbent dosage, stirring speed, and pH of solution was studied. The obtained results were later compared with adsorption isotherms (i.e. Langmuir and Freundlich). The Freundlich model was found to fit closely with results due to heterogeneous adsorption of dye molecules. Finally, virgin activated carbon and dye adsorbed activated carbon were tested for desorption behavior using differential scanning calorimetry and thermo gravimetric analysis. The significant reduction in desorption enthalpy from 172.46 to 52.43 J g-1 is attributed to less adsorption energies of dye molecules on the surface of activated carbon due to nonhomogeneous distribution of active sites. [ABSTRACT FROM AUTHOR]