Theoretical Investigation for Two-state Reactivity of CO_2 Hydrogenation Catalyzed by Ru in Gas Phase

Gas-phase CO_2 catalyzed activation hydrogenation by Ru atoms was studied with density functional theory. Based on the structure optimization of different potential energy surfaces,there are two crossing points between singlet and triplet potential energy surfaces and there is a crossing point between quintet and triplet potential energy surfaces in the whole catalytic cycle. Spin transition probabilities in the vicinity of the intersections have been calculated by the Landau-Zener model theory. There are three minimum energy crossing points（MECPs） with strong spin-orbital coupling effect and higher spin transition probability,and all spin inversion occurred in s orbital and different d orbitals of ruthenium,indicating this is a typical two-state reactivity（TSR） reaction. Finally,the lowest energy reaction path is ensured.

Effect of Carbon Properties on Melting Behavior of Mold Fluxes for Continuous Casting of Steels

During continuous casting of steel, the properties of mold fluxes strongly affect the casting performance, steel quality and environment of casting operation. The high temperature microscopy technique was used to investigate the melting behaviour of mold fluxes, and drip test method was used to determine their melting rate. The results showed that free carbon is a dominant factor in governing the melting behaviour of fluxes, and the melting rate is increased with increasing carbon reactivity and decreasing carbon content.

Adsorption Properties and Quantum Molecular Descriptors of the Folic Acid Drug Adsorbed onto Zigzag and Armchair Single Walled Carbon Nanotubes:DFT Simulations

The adsorption behavior of folic acid onto（5,0） zigzag and（5,5） armchair carbon nanotube（SWCNT） has been investigated using B3 LYP density functional at the 6-31G＊ level. The adsorption energies,molecular orbital analysis and structural changes at the adsorption site are indicative of covalent adsorption on the zigzag SWCNT surface,while the adsorption is physical on the armchair SWCNT surface. The density of states（DOS） Plot and the quantum molecular descriptors（QMD） are witness to the significant changes in the electronic properties of SWCNT systems after the attachment of adsorbed species to the tube surface. According to the calculated results,the single-walled carbon nanotubes are expected to be a potential efficient adsorbent for the adsorption of folic acid drug and also can be used as a suitable drug delivery vehicle within biological systems.

PPC-based Reactive Hot Melt Polyurethane Adhesive(RHMPA)--Efficient Glues for Multiple Types of Substrates

Tens of billion metric tons of anthropogenic CO_2 discharged from the burning of fossil fuels lead to an enormous environmental and resource burden. It is charming to transform CO_2 to desirable, economical chemicals and materials. Poly（propylene carbonate）（PPC） is an emerging CO_2-based material. Herein, we report the design, synthesis and characterization of the reactive hot melt polyurethane adhesive（RHMPA） based on PPC polyol. The resultant RHMPAs exhibit good adhesion properties to multiple substrates including plastics（PC, PMMA, ABS） and metals（aluminium, steel）, which is comparable to or even better than conventional RHMPAs prepared from petro-based polyol. Furthermore, the PPC-based RHMPAs have tunable mechanical properties, and are thermally stable in the typical working range of bonding process（up to 270 °C）. The study is expected to expand the applications of PPC and provide a new type of CO_2-based renewable and eco-friendly materials.

Removal of 2-ClBP from soil–water system using activated carbon supported nanoscale zerovalent iron

We explored the feasibility and removal mechanism of removing 2-chlorobiphenyl（2-Cl BP）from soil–water system using granular activated carbon（GAC） impregnated with nanoscale zerovalent iron（reactive activated carbon or RAC）.The RAC samples were successfully synthesized by the liquid precipitation method.The mesoporous GAC based RAC with low iron content（1.32%） exhibited higher 2-Cl BP removal efficiency（54.6%） in the water phase.The result of Langmuir–Hinshelwood kinetic model implied that the different molecular structures between 2-Cl BP and trichloroethylene（TCE） resulted in more difference in dechlorination reaction rates on RAC than adsorption capacities.Compared to removing2-Cl BP in the water phase,RAC removed the 2-Cl BP more slowly in the soil phase due to the significant external mass transfer resistance.However,in the soil phase,a better removal capacity of RAC was observed than its base GAC because the chemical dechlorination played a more important role in total removal process for 2-Cl BP.This important result verified the effectiveness of RAC for removing 2-Cl BP in the soil phase.Although reducing the total RAC removal rate of 2-Cl BP,soil organic matter（SOM）,especially the soft carbon,also served as an electron transfer medium to promote the dechlorination of 2-Cl BP in the long term.

Reactive poly(divinyl benzene-co-maleic anhydride) nanoparticles:Preparation and characterization

Polymeric nanoparticles（NPs）have drawn great interest in the past few years due to their potential applications in the felds of biomedical and optical technologies.However,it is still a challenge to prepare functional polymeric NPs,especially for particle diameters smaller than 50 nm.In this work,we demonstrate a one-pot method to fabricate reactive poly（divinyl benzene-co-maleic anhydride）NPs（PDVBMAH NPs）through a self-stable precipitation polymerization process.The size and morphology of these PDVBMAH NPs were characterized in detail by scanning electronic microscopy,and their chemical structure was determined by IR.The results showed that these NPs were highly cross-linked and their diameter was about 30 nm with narrow distribution.Additionally,the DVB and MAH endow the NPs with reactive surface anhydride and pendant vinyl groups,and these particles could be further functionalized through reaction of these groups.A plausible pathway was proposed for the formation of PDVBMAH NPs.