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High temperature stage microscope was applied to observe morphology evolution of flaky char particles during gasification. Raman spectroscopy was used to analyze crystalline structures of gasification semicoke. Effect of gasification temperature (1000–1200°C) and initial equivalent diameter (1.00–1.60 mm) on morphology and structure evolution were examined. The results show that particle shrinkage in later stage of gasification is more intense than that in early stage. Within tested gasification temperature, the particle ASR (area shrinkage ratio) and VSR (volumetric shrinkage ratio) decrease with increasing temperature. The initial particle size of char has a significant effect on particle shrinkage. At 1100°C the shrinkage trend of particle marks a turning point at initial diameter of 1.30 mm. The variation of char apparent density is dominated by carbon consumption. When the carbon conversion reaches 80%, the apparent density ratio linearly decreases below 0.4. At the same gasification temperature, with increasing carbon conversion the graphitization of char reduces first and then increases, while the amorphous carbon is opposite.

A one-dimensional manganese(II) complex, [Mn(L2)]n (1, HL = 4-pyridyl-NH-1,2,3-triazole), has been hydrothermally synthesized at 120 °C. In the structure of 1, the Mn(II) ions are octahedral coordinated and further bridged by L− ligands, forming a rigid 1D ribbon coordination chain. Varieties of supramolecular interactions, such as hydrogen bonds and C H ⋯ π interactions, play an important role on the stabilization of the structures. As revealed by magnetic measurement, complex 1 displays weak antiferromagnetic interaction with θ = –4.83 K, the best fit using Fisher's 1D Heisenberg model gives the intrachain magnetic coupling constant J = –0.21 cm− 1 above 30 K due to the neighboring Mn(N–N)2Mn rings twisted in the angle of almost 90°.

Cobalt oxide and porous carbon materials are desirable catalysts for peroxymonosulfate (PMS) advanced oxidation reaction in the degradation of organic pollutants. Herein, carbon-coated Co3O4 (Co3O4/C) mounted biochar (BC) composites (Co3O4/C-BC) with a three-dimensional spongy-like network were constructed by driving a dual-precursors of zeolitic imidazolate framework (ZIF-67) and Eichhornia crassipes. Considering the unique structures and compositions, the Co3O4/C-BC composites enhanced the dispersion of Co3O4/C nanoparticles, minimized the Co leaching, mediated the size of Co3O4/C nanoparticles, and enhanced the overall catalytic activity. Co3O4/C-BC effectively activated PMS for bisphenol A (BPA) degradation along with satisfactory reusability in advanced oxidation reaction. Electron paramagnetic resonance and radical quenching tests revealed that the generation and effect of sulfate and hydroxyl radicals in reaction process. This work not only provided a promising catalyst for the degradation of organic pollutants but also expanded BPA degradation pathway and PMS activation mechanism.

Functionalized biochar as a great potential purification material towards removal of contaminants form environment. Herein, Fe2O3/TiO2 functionalized biochar (Fe2O3/TiO2-BC) was fabricated through one-step pyrolysis of Fe2+–Ti4+ laden tea leaves biomass under air environment. The morphology, structure, and chemical state of Fe2O3/TiO2-BC were systematically characterized. Fe2O3/TiO2-BC exhibits higher degradation efficiency for dye pollutants via synergistic effect of sorption and oxidation in the Fenton system. The total organic carbon (TOC) removal efficiencies reached above 65 %. The degradation mechanisms and pathways of dyes (methylene blue (MB) selected as model), and the effects of the amount of H2O2, catalyst dosage, temperature, and initial pH value on the degradation processes were also studied. The electron spin resonance (ESR) and radicals quenching experimental results confirmed that the dominant radical species was hydroxyl radical. Additionally, Fe2O3/TiO2-BC could be easily regenerated by washing with water/ethanol mixture. Overall, these results indicate that the Fe2O3/TiO2-BC provides great potential for removing dye pollutants from water.

Black soil (Mollisol) is one of the main soil types in northeastern China. Biolog and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) methods were used to examine the influence of various fertilizer combinations on the structure and function of the bacterial community in a black soil collected from Harbin, Heilongjiang Province. Biolog results showed that substrate richness and catabolic diversity of the soil bacterial community were the greatest in the chemical fertilizer and chemical fertilizer+manure treatments. The metabolic ability of the bacterial community in the manure treatment was similar to the control. DGGE fingerprinting indicated similarity in the distribution of most 16S rDNA bands among all treatments, suggesting that microorganisms with those bands were stable and not influenced by fertilization. However, chemical fertilizer increased the diversity of soil bacterial community. Principal component analysis of Biolog and DGGE data revealed that the structure and function of the bacterial community were similar in the control and manure treatments, suggesting that the application of manure increased the soil microbial population, but had no effect on the bacterial community structure. Catabolic function was similar in the chemical fertilizer and chemical fertilizer+manure treatments, but the composition structure of the soil microbes differed between them. The use of chemical fertilizers could result in a decline in the catabolic activity of fast-growing or eutrophic bacteria.

Burns caused by hot coolant from the reservoir of motorfarming tricycles have not been reported previously. We performed retrospective studies of such cases in 126 patients with complete records in rural areas of China. The majority of victims were unmarried (59.5%), young (40 years,20, 55.6%), and male (male to female ratio 9:1). The burn accident occurred mostly during the busy seasons of spring and summer (66.7%). The mechanism of injury was usually the same. The drivers were trapped under the farming tricycle in a traffic accident and then hot coolant leaked from the mouth of the coolant, resulting in long contact with the hot fluid. The burn wounds were located mostly on the areas of the buttocks and lower extremities (especially on the thigh) (64.3%). The generally burned patients had moderate burn areas, about 20-50% total burn surface area (TBSA) of deep partial thickness or full thickness burn wound. For the purpose of decreasing the number of burns presenting, or at least making them less severe, the suggestions include: (1) the design of motorfarming tricycle should be changed; obviously separation of the coolant tank from the seat is the most important factor in reducing such burns. (2) Road conditions should be improved to reduce traffic accidents and loading regulations introduced. (3) Traffic control should be enhanced, especially in rural areas.