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For the purpose of investigating the fractal characteristics of pores in Taiyuan formation shale, a series of qualitative and quantitative experiments were conducted on 17 shale samples from well HD-1 in Hedong coal field of North China. The results of geochemical experiments show that Corresponding author. This is an Open Access article published by World Scientific Publishing Company. It is distributed under the terms of the Creative Commons Attribution 4.0 (CC-BY) License. Further distribution of this work is permitted, provided the original work is properly cited. 1840006-1Fractals 2018.26. Downloaded from www.worldscientific.com by 13.66.222.141 on 06/06/19. Re-use and distribution is strictly not permitted, except for Open Access articles. K. Li et al.Total organic carbon (TOC) varies from 0.67% to 5.32% and the organic matters are in the high mature or over mature stage. The shale samples consist mainly of clay minerals and quartz with minor pyrite and carbonates. The FE-SEM images indicate that three types of pores, organicrelated pores, inorganic-related pores and micro-fractures related pores, are developed well, and a certain number of intragranular pores are found inside quartz and carbonates formed by acid liquid corrosion. The pore size distributions (PSDs) broadly range from several to hundreds nanometers, but most pores are smaller than 10 nm. As the result of different adsorption features at relative pressure (0-0.5) and (0.5-1) on the N 2 adsorption isotherm, two fractal dimensions D 1 and D 2 were obtained with the Frenkel-Halsey-Hill (FHH) model. D 1 and D 2 vary from 2.4227 to 2.6219 and from 2.6049 to 2.7877, respectively. Both TOC and brittle minerals have positive effect on D 1 and D 2 , whereas clay minerals, have a negative influence on them. The fractal dimensions are also influenced by the pore structure parameters, such as the specific surface area, BJH pore volume, etc. Shale samples with higher D 1 could provide more adsorption sites leading to a greater methane adsorption capacity, whereas shale samples with higher D 2 have little influence on methane adsorption capacity.

A group of aptamers possessing high specificity and affinity for creatine kinase MB (CKMB) was obtained by magnetic systematic evolution of ligands by exponential enrichment. Two aptamers (referred to as C.Apt.21 and C.Apt.30) were found to possess adequately low K values. They form a well suited pair for CKMB binding. By using fluorescent microspheres, an aptamer-based lateral flow assay was developed. It is portable, economical, and sensitive. The limit of detection for CKMB is as low as 0.63 ng·mL, and the assay works in the 0.005 - 2 μg·mL CKMB concentration range. The method is specific for CKMB, and biomarkers for AMI (such as cardiac troponin I and myoglobin) and serum do not interfere. The strip is highly accurate as shown by analysis of spiked serum samples which gave recoveries ranging between 88 and 117%. Graphical Abstract Schematic of the test strip and sandwich aptamer-based fluorometric lateral flow assay for creatine kinease. The detection is based on the specific affinity between CKMB and selected aptamers to form a sandwich structure.

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Microstructural characterisation of organic matter pores in coal-measure shale.

Using the first-principles calculation, we investigate the adsorption of CO and NO on (8, 0) silicon nanotubes (SiNTs). The detailed analysis of the structural and electronical properties of various optimized configurations is performed. The results show that CO molecule can be chemisorbed on SiNT with the C atom bonding with the Si atom of the tubular surface when CO is located on the top site, accompanying with the binding energy of 1.559 eV and charge transfer of 0.658|e|, which are larger than the results of other configurations. For the SiNT-NO systems, there exist four strong chemical adsorption configurations. The most stable configuration is the N atom bonding with two Si atoms on the bridge site. The binding energy is 2.135 eV and charge transfer is 2.064|e|. In addition, it is found that both the C–O and N–O bonds are elongated when CO and NO are chemisorbed on SiNT. Compared to carbon nanotubes (CNTs) or silicon carbon nanotubes (SiCNTs), the SiNTs have stronger interaction with the CO and NO and can provide more sensitive signal for CO and NO sensing. In particular, the semiconducting (16, 0) SiNT would become metallic after adsorption CO, and the SiNTs after adsorption of NO would be magnetic, which can serve as a sensitive signal for CO or NO sensing. In short, the SiNTs with the semconducting structure are a very promising candidate for CO and NO sensing and detection.

Trantinterol is a novel β(2)-adrenoceptor agonist used for the treatment of asthma. The aim of this study is to identify the metabolites of trantinterol using liquid chromatography tandem mass spectrometry (LC-MS/MS), to isolate the main metabolites, and confirm their structures by nuclear magnetic resonance (NMR). Urine, feces, bile, and blood samples of rats were obtained and analyzed. Reference standards of six metabolites were achieved with the combination of chemical synthesis, microbial transformation, and the model systems of rats. Moreover, in order to investigate the phase I metabolism of trantinterol in humans and to study the species differences between rats and humans, incubations with liver microsomes were performed. The biotransformation by a microbial model Cunninghamella blakesleana AS 3.970 was also studied. A total of 18 metabolites were identified in vivo and in vitro together, 13 of which were newly detected. Three phase I metabolites were detected in vivo and in vitro as well as in the microbial model, including the arylhydroxylamine (M1), the tert-butyl hydroxylated trantinterol (M2) and the 1-carbonyltrantinterol (M3). Another important pathway in rats is glutathione conjugation and further catabolism and oxidation to form consecutive derivatives (M4 through M10). Other metabolites include glucuronide, glucoside, and sulfate conjugates. The results of in vitro experiments indicate no species difference exists among rats, humans, and C. blakesleana AS 3.970 on the phase I metabolism of trantinterol. Our study provided the most comprehensive picture for trantinterol in vivo and in vitro metabolism to this day, and may predict its metabolism in humans.