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To the gas system of multi-coalbeds overlay in Zhina coalfield, the initial proposals about coalbed methane (CBM) exploitation, based on a large number of coalfield geological exploration data and the results obtained in coalbed methane exploration recently, was proposed through the analysis of coal reservoir's flexibility energy on horizontal and that of different gas systems on vertical, respectively. The study revealed that Zhongzhai exploration area is the independent gas system of multi-coalbeds overlay. The relation of methane flexibility energy and burial depth of a coalbed show intense fluctuations among the four gas systems, however, methane flexibility energy is increasing with burial depth of coalbed in every different gas system. Adopting subsection fracturing and drainage pattern, the first gas system was the best fit for CBM exploitation. Zhi-2 well, a unified gas system of multi-coalbeds overlay, is located in Zhuzang syncline, of which coal reservoir's flexibility energy is increasing with...

Comparative pharmacokinetic profiles of diaveridine following single intravenous and oral dose of 10 mg/kg body weight in healthy pigs and chickens were investigated, respectively. Concentrations of diaveridine in plasma samples were determined using a validated high-performance liquid chromatography-ultraviolet (HPLC-UV) method. The concentration-time data were subjected to noncompartmental kinetic analysis by WinNonlin program. The corresponding pharmacokinetic parameters in pigs or chickens after single intravenous administration were as follows, respectively: t1/2β (elimination half-life) 0.74 ± 0.28 and 3.44 ± 1.07 h; Vd (apparent volume of distribution) 2.70 ± 0.99 and 3.86 ± 0.92 L/kg; ClB (body clearance) 2.59 ± 0.62 and 0.80 ± 0.14 L/h/kg; and AUC0-∞ (area under the blood concentration vs. time curve) 4.11 ± 1.13 and 12.87 ± 2.60 μg∙h/mL. The corresponding pharmacokinetic parameters in pigs or chickens after oral administration were as follows, respectively: t1/2β 1.78 ± 0.41 and 2.91 ± 0.57 h; Cmax (maximum concentration) 0.43 ± 0.24 and 1.45 ± 0.57 μg/mL; Tmax (time to reach Cmax ) 1.04 ± 0.67 and 3.25 ± 0.71 h; and AUC0-∞ 1.33 ± 0.55 and 9.28 ± 2.69 μg∙h/mL. The oral bioavailability (F) of diaveridine in pigs or chickens was determined to be 34.6% and 72.2%, respectively. There were significant differences between the pharmacokinetics profiles in these two species.

Osmotic stress at elevated osmotic pressure was used to stimulate saponin production in Panax ginseng cell cultures. The addition of 0.3 M sorbitol to culture at the time of inoculation, raising the medium osmolality by about 75% (from 150 to 260 mmol/kg), enhanced the saponin accumulation but depressed the cell growth, resulting in no improvement of the volumetric saponin yield of culture. The feeding of sorbitol (0.2–0.3 M, 36.4–54.6 g/L) to culture during the stationary growth phase increased both the saponin content of cell (45–50%) and the volumetric yield (36–38%). With combined feeding of sorbitol (0.2 M) and growth nutrients, sucrose (30 g/L) + casein hydrolysate (0.5 g/L), about 2 days before the stationary phase, the volumetric saponin yield was increased 3.5-fold, 1130.8 mg/L versus the control culture of 251.2 mg/L. Sorbitol in the culture also induced two characteristic stress responses of plant cells, the increase in phenylalanine ammonium-lyase (PAL) activity and the production of reactive oxygen species. This suggests that the stimulated saponin accumulation was part of the cell response to the osmotic stress.

Molecular dynamics simulations have been performed to study the mechanical properties of armchair-type single-walled and multiple-walled carbon nanotubes under tensile loading with and without hydrogen storage. Advanced bond order potentials were used in the simulations. Hydrogen molecules stored inside or outside nanotubes reduced the fracture strength of nanotubes. During the deformation, some C-C bonds were broken and reconstructed. If hydrogen. molecules were around, hydrogen atoms would compete with the carbon atoms, to form the H-C bonds, which reduces the mechanical strength of nanotubes. Such detrimental effect of hydrogen is enhanced if the curvature of the tubes is increased, or if hydrogen is stored in a multiple-walled carbon nanotube.

In catalysis applications, it is desirable to have nanorods of smaller diameter. However, if the separation of nanorods is smaller than their diameter, nanorods will merge to become dense films. The separation of nanorods derives from the separation of nucleating clusters on the substrate. This letter reports a theory of the smallest separation of nanorods. This theory is in closed form and is verified by accompanying lattice kinetic Monte Carlo simulations. The theoretical prediction of transition from nanorods to dense films—when the separation of nanorods is smaller than their diameter—is in good agreement with in-house experimental observation.

Using classical molecular statics simulations, we show that nanoplate elasticity strongly depends on surface reconstruction and alignment of bond chains. Because of its well-established surface reconstructions and the readily available interatomic potential, diamond-cubic silicon is the prototype of this study. We focus on silicon nanoplates of high-symmetry surfaces, {111} and {100}; with 7×7 and 2×1 reconstructions. Nanoplates with unreconstructed {111} surfaces are elastically stiffer than bulk. In contrast, the same nanoplates with 7×7 reconstructed {111} surfaces are elastically softer than bulk. On {100} surfaces, the 2×1 surface reconstruction has little impact. The bond chains are along one of the two ⟨110⟩ directions, making the two ⟨110⟩ directions nonequivalent. The alignment of the bond chains on the opposite surfaces of a nanoplate dictates its elastic anisotropy. The sensitivity of nanoplate elasticity on details of surface atomic arrangements may impact the application of nanoplates (or nan...