Fine Structure Characterization of Representative Coal-Bearing Rocks of the Late Carboniferous Taiyuan Formation in Huainan Coalfield: Combined SEM, FESEM, and µCT Techniques.

Pores and fractures are important channels for coalbed methane (CBM) storage, seepage, and production, and accurate characterization of the microstructure of coal-bearing rock strata is of great significance for CBM exploration and development. Taking the coal-bearing rocks of the Late Carboniferous Taiyuan Formation in the Huainan coalfield as the research object, accurate characterization of the organic macerals, microstructure, and mineral distribution of sandstone, coal, and sandy mudstone was achieved using a multiscale combination of polarization microscopy (POM), X-ray diffraction (XRD), scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM), and X-ray computed tomography (µCT). The thin section identification results indicated that the organic matter in the coal measures rocks of the Taiyuan Formation was well developed and mainly composed of vitrinite, followed by fusinite and exinite, and in addition, there was a distribution of bituminite and sapropelite. The mineral composition of the rocks was dominated by quartz, calcite, siderite, and clay minerals, in addition to plagioclase and ankerite in the fine sandstone. In terms of pore and fracture development, all types of rocks were highly developed with nanoscale and micrometer-scale pores and of mostly irregular shapes, and all types of rocks had fracture development except for medium sandstone. The above-mentioned results show that the Late Carboniferous Taiyuan Formation in the Huainan coalfield has good space for CBM storage and transportation and has certain potential for CBM development. This study provides theoretical guidance for unconventional oil and gas exploration and development in the Huainan coalfield.

Laser Shock Fabrication of Nitrogen Doped Inverse Spinel Fe3O4/Carbon Nanosheet Film Electrodes towards Hydrogen Evolution Reactions in Alkaline Media.

The reliable and cost-effective production of high-performance film electrodes for hydrogen evolution reactions remains a challenge for the laser surface modification community. In this study, prior to a thermal imidization reaction, a small number of Fe3O4 nanoparticles were vortexed into a poly(amic acid) (PAA) prepolymer, and the achieved flat composite film was then ablated by a 1064 nm fiber laser. After laser irradiation, the hierarchical architectures of carbon nanosheets decorated with Fe3O4 nanoparticles were generated. Although pure polyimide (PI) film and laser carbonized PI film, as well as bare Fe3O4, showcase poor intrinsic catalytic activity toward alkaline hydrogen evolution reactions, our laser-derived Fe3O4/carbon nanosheet hybrid film demonstrated enhanced electrocatalytic activity and stability in 1 M KOH electrolyte; the overpotential(η10) reached 247 mV when the current density was 10 mA cm-2 with a slight current decay in the chronoamperometric examination of 12 h. Finally, we proposed that the substitution of N to O in Fe-O sites of trans spinel structured magnetite would be able to modulate the free energy of hydrogen adsorption (ΔGH*) and accelerate water dissociation.

Coal utilization in China: environmental impacts and human health.

Coal is one of the major energy resources in China, accounting for approximately 70 % of primary energy consumption. Many environmental problems and human health risks arise during coal exploitation, utilization, and waste disposal, especially in the remote mountainous areas of western China (e.g., eastern Yunnan, western Guizhou and Hubei, and southern Shaanxi). In this paper, we report a thorough review of the environmental and human health impacts related to coal utilization in China. The abundance of the toxic trace elements such as F, As, Se, and Hg in Chinese coals is summarized. The environmental problems (i.e., water, soil, and air pollution) that are related to coal utilization are outlined. The provenance, distributions, typical symptoms, sources, and possible pathways of endemic fluorosis, arsenism, and selenosis due to improper coal usage (briquettes mixed with high-F clay, mineralized As-rich coal, and Se-rich stone coal) are discussed in detail. In 2010, 14.8, 1.9 million, and 16,000 Chinese people suffered from dental fluorosis, skeletal fluorosis, and arsenism, respectively. Finally, several suggestions are proposed for the prevention and treatment for endemic problems caused by coal utilization.

Atmospheric emissions of F, As, Se, Hg, and Sb from coal-fired power and heat generation in China.

Coal is one of the major energy resources in China, with nearly half of produced Chinese coal used for power and heat generation. The large use of coal for power and heat generation in China may result in significant atmospheric emissions of toxic volatile trace elements (i.e. F, As, Se, Hg, and Sb). For the purpose of estimating the atmospheric emissions from coal-fired power and heat generation in China, a simple method based on coal consumption, concentration and emission factor of trace element was adopted to calculate the gaseous emissions of elements F, As, Se, Hg, and Sb. Results indicate that about 162161, 236, 637, 172, and 33 t F, As, Se, Hg, and Sb, respectively, were introduced into atmosphere from coal combustion by power and heat generation in China in 2009. The atmospheric emissions of F, As, Se, Hg, and Sb by power and heat generation increased from 2005 to 2009 with increasing coal consumptions.

Solanum nigrum Linn. water extract inhibits metastasis in mouse melanoma cells in vitro and in vivo.

Metastatic melanoma is an aggressive skin cancer notoriously resistant to current cancer therapies. Thus, new treatment strategies are urgently needed. Solanum nigrum Linn., commonly used in Oriental medicine, has showed antineoplastic activity in human cancer cell lines. The aim of this study was to evaluate the inhibitive effect of S. nigrum Linn. water extract (SNWE) on melanoma metastasis and dissect the underlying mechanisms of SNWE actions. B16-F1 cells were analyzed for migrating and invasive abilities with SNWE treatment, and several putative targets involved in metastatic melanoma were examined. In parallel, primary mouse xenograft and lung metastasis of melanoma models were established to examine the therapeutic potential of SNWE. The results indicated SNWE significantly inhibited B16-F1 cell migration and invasion. Meanwhile, decreased Akt activity and PKCα, Ras, and NF-κB protein expressions were detected in dose-dependent manners. In line with this notion, >50% reduced tumor weight and lung metastatic nodules were observed in 1% SNWE fed mice. This was associated with reduced serum MMP-9 as well as Akt activity and PKCα, Ras, and NF-κB protein expressions. Thus, this work indicates SNWE has potential application for treating metastatic melanoma.