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Density functional theory method is used to explore the mechanism of dissociative adsorption of methane (CH₄) on S_A type stepped Si(100) surface. Two reaction paths are described that produce CH₃ and hydrogen atom fragments adsorbed on the dimer bonds present on each terraces. It has been found that, in the initial stage of the carbonization of stepped Si(100) surface, the CH₃ and H fragments bound to the Si dimer atoms by following the first reaction path.

SKS active carbon, prepared by dehydrogenation of the polystyrene–divinylbenzene copolymer, as a model sample of highly amorphous carbons, has been examined by scanning electron microscopy, transmission electron microscopy, and energy dispersive X-ray methods, indicating a nanostructural nonperiodic character of the resulting product. No crystalline-like particles are experimentally found in the bulk. The PSDVB copolymer dehydrogenation has been quantum chemically (QC) simulated to describe the interconnecting amorphous phase. A set of clusters with a different degree of carbonization has been QC evaluated. The first level model of the amorphous active carbon has been proposed.

In this study, halloysite nanotubes (HNTs), an environmentally friendly inorganic nanomaterial, was added to epoxy matrix glass and basalt fiber reinforced plastics (GFRP and BFRP) by heat treatment of HNTs with crystalline and amorphous structure at $700^{\circ }\mathrm{\text{C}}$ and $1000^{\circ }\mathrm{\text{C}}$. Their interfacial bonding strength and effect of HNTs before and after carbonization by flame were analyzed. We found that the HNT/epoxy formed a physical barrier on the surface because of the char generated by carbonization. The barrier showed excellent thermal stability and limiting oxygen index in BFRP. The flexural strength after carbonization was low in the amorphous 1000HTHNT-BFRP with strong interfacial bonding. In other words, the morphological structure of the HNTs helped the improvement of the interfacial bonding strength; hence, the reinforcing effect of the HNTs on the thermal stability and mechanical strength before and after carbonization can be controlled.

In this paper, the durability of steel fiber reinforced concrete/SFRC is tested under the combined effects of carbonization and acid rain erosion. Mass loss rate, splitting tensile strength loss rate, eroded thickness and neutralization depth were taken as evaluation index. Test results indicated that the concrete mass loss rate, splitting tensile strength loss rate, and eroded thickness of SFRC under the multi-combined effects of acid rain and carbonization are greater than that of SFRC affected by the acid rain; the neutralization depth of SFRC are larger under the multi-factor effects of acid rain and carbonization compared to the superposition of them. According to the analysis of combined effects, the carbonization and acid rain has almost equal contribution to the neutralization of concrete. Proper mixture of steel fiber can effectively inhibit the erosion of original concrete under the effect of acid rain and reduce the neutralization depth. According to the varied mixing proportions in the test, the SFRC with the steel fiber mixing proportions of 1.5% has the best durability.

Lignin-based carbon nanomaterials (LCN) were prepared from alkaline lignin (AL) by hydrolysis, spray drying and high temperature treatment. Then, the physical and chemical structures of LCN were analyzed by SEM, BET, organic element analyzer, FTIR, Raman, UV–vis and XPS. The results showed that the yield of LCN was 26.34% of the mass of AL. The particle size of LCN was 120–350 nm, and three to seven particles with diameter of 40–100 nm are accumulated. Its specific surface area was 374.74 m²/g with the average pore size of 4.79 nm. The ratio of sp² to sp³ was 1.39 and the band gap was 3.42 eV. The simplified apparent formula of LCN was C${}_{21}$H₄O with an unsaturation of 20, containing C–C, C=C, C–O, O=C–O and C–H groups. The chemical structure model of LCN was constructed by Chem 3D software. Therefore, this study successfully prepared a special material and analyzed its physical and chemical structure, which was conducive to the structural analysis of carbon nano-materials.

Periconia sp. (endophytic fungus) biomass was effectively explored as the source for the fabrication of carbon nanostructures by one-step carbonization at 800^∘C for 2h. The morphological characterizations of obtained biocarbon through SEM and TEM analysis revealed the formation of 2D-platelet-like carbon nanostructures. Further, its phase and structural characterizations through Raman and XRD analysis also supported the same. The obtained biocarbon was coated upon mung bean seeds to investigate its influence on germination and growth. The preliminary results revealed that the biocarbon accelerates seed germination and growth behavior of mung bean, which was observed by means of length, mass, and surface area profile respectively for the the plant’s shoots, roots, and leaves. It was also found that the germination and growth effects are highly dependent on the concentration of the biocarbon, in which 1000mg of biocarbon in 50mL of water is found to be higher than the lower concentration for seed germination and seedling growth.

Recycled Aggregate Concrete (RAC) was prepared with different recycled aggregate replacement ratio, 0, 30%, 70% and 100% respectively. The performances of RAC were examined by the freeze-thaw cycle, carbonization and sulfate attack to assess the durability. Results show that test sequence has different effects on the durability of RAC; the durability is poorer when carbonation experiment was carried out firstly, and then other experiment was carried out again; the durability is better when recycled aggregate replacement ratio is 70%.

Coal tar pitch (CTP) was modified with phenolic resin (PF). The parent CTP and modified CTP were carbonized at different temperatures, then the products were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). The results show that pyrolytic carbon of the parent CTP had formed lamella and banded structure. Modified CTPs’ lamella and banded structures were easier to be formed. Also, high temperature is good for the graphitization of CTP, but it is not advantageous to form the lamella structure.

Biomasses such as woody waste and sewage sludge can be converted to renewable energy source by using carbonization process. Carbonization process is carried out to obtain energy characteristics of carbonization residue from the mixture of woody waste and sewage sludge. The effects of temperature, time, and sewage sludge content on carbonization process are estimated by energy characteristics of the residue such as heating, yield, and fuel ratio. From the results of energy characteristics of residue, the optimum content of sewage sludge in carbonization process can be decided by 30%. At the optimum content of sewage sludge in carbonization process, the carbonization residue of mixture of woody waste and sewage sludge can be deserved to use one of renewable energy sources from the results of fuel ratio and total heating value.