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It is rather essential to design porous carbon adsorbents with high CO2 capture performance for improving global warming and climate change. Activated carbon spheres with high specific surface area and hierarchical porous texture were prepared from polystyrene-based macroreticular resin spheres due to their low ash and mechanical stability by air pre-oxidization and steam activation. The as-prepared carbon spheres had a specific surface area of 1274.95 m2 g−1, total pore volume of 1.09 cm3 g−1 and micropore volume of 0.47 cm3 g−1. Moreover, these carbon spheres showed a hierarchical porous texture composed of ultrafine micropores (0.5–1 nm), micropores (1–2 nm), mesopores (10–50 nm) and macropores (50–100 nm). A CO2 adsorption capacity of 2.82 mmol g−1 for carbon spheres can be obtained at 30 °C and 1 atm. Further, after introducing nitrogen-containing functional groups by gaseous ammonia at 600 °C, these carbon spheres (NPSRCSs) exhibited a high CO2 adsorption capacity of 3.2 mmol g−1. In addition, excellent cyclic stability, low hygroscopicity and regenerability temperature suggested these carbon spheres were favorable for CO2 capture.

In order to solve the problems due to the thickening of drilling fluids at low temperatures caused by the use of high-molecular-weight polymer coating agents in offshore deep-sea oil and gas drilling, a low-molecular-weight polymer coating agent named PADA was synthesized with acrylamide, methacryloxyethyltrimethyl ammonium chloride, and 2-acrylamido-2-methyl propane sulfonic acid. The PADA polymer was characterized with Fourier transform infrared spectroscopy and gel permeation chromatography. The shale inhibition effects of the PADA polymer and associated mechanisms were investigated by shale recovery and expansion experiments, transmission electron microscopy observation, particle size and zeta potential analysis, and interlayer spacing measurements. In addition, the effects of the coating agent on the filter cakes and the low temperature rheological properties of bentonite mud were also tested, and the polymer biodegradability was evaluated. The results showed that the molecular weight of the PADA polymer was 265,000 D, which was significantly lower than that of the traditional coating agents. The PADA had similar effects as two typical commercial products CAP and HPAM on inhibiting the hydration dispersion of shales and performed better than another product PAM. The inhibition effect was achieved by the polymer absorption onto the clay particles through both hydrogen bonding and the electrostatic interactions. The viscosity of bentonite mud containing PADA was much lower than that of mud with other coating agents at 4 °C, so the serious thickening caused by traditional coating agents at a low temperature could be avoided. In addition, it is relatively easily biodegraded.

Pigeon paramyxovirus-1 (PPMV-1) is a strain of Newcastle disease virus (NDV) that has adapted to infect pigeons and poses a constant threat to the commercial poultry industry. Early detection via rapid and sensitive methods, along with timely preventative and mitigating actions, is important for reducing the spread of PPMV-1. Here, we report the development of a TaqMan loop-mediated isothermal amplification assay (TaqMan-LAMP) for rapid and specific detection of PPMV-1 based on the F gene. This system makes use of six novel primers and a TaqMan probe that targets nine distinct regions of the F gene that are highly conserved among PPMV-1 isolates. The results showed that the limit of detection was 10 copies μL-1 for PPMV-1 cDNA and 0.1 ng for PPMV-1 RNA. The reaction was completed within 25 min and was thus faster than conventional RT-PCR. Moreover, no cross-reactions with similar viruses or with peste des petits ruminants virus (PPRV) or NDV LaSota vaccine strains were observed under the same conditions. To evaluate the applicability of the assay, the TaqMan-LAMP assay and a commercial RT-PCR assay were compared using 108 clinical samples, and the concordance rate between two methods was found to be 96.3%. The newly developed PPMV-1 TaqMan-LAMP assay can therefore be used for simple, efficient, rapid, specific, and sensitive diagnosis of PPMV-1 infections.

In this paper, we establish the local well-posedness of strong solutions to the three dimensional viscous non-resistive MHD system with internal surface wave in low regularity Sobolev spaces. Due to the absence of magnetic diffusion, the proof will be based on the new Stokes estimates involving in optimal surface regularity, the weighted energy estimates and the higher order horizontal regularity estimates.

Sodium-ion batteries (SIBs) have drawn more attention to serve as one of the promising energy storage devices owing to the abundance of sodium resources and similar characters with lithium element. Hard carbon materials derived from biomass or biomass waste have been considered to act as candidate anode materials for SIBs. In this paper, we have successfully prepared curly hard carbon materials using pistachio shells as biomass template via a two-step approach including hydrothermal treatment and following a pyrolysis process at various temperatures. Physical properties of pistachio shell-derived hard carbons (PSHCs) including microstructure, morphology and pore size distribution are evaluated by X-ray diffraction, Raman spectrum and N2 sorption analysis. The PSHCs carbonized at 1000 °C (PSHC-1000) with average micropores of 0.7398 nm and larger interlayer space of the (002) crystal plane deliver the highest reversible capacity of 317 mAh g−1 at 0.1C, also show the excellent long-term cycling and rate performances. Electrochemical impedance spectroscopy technology is introduced to study the kinetics parameters during the first sodiation process of PSHC-1000 electrode, and also to compare the resistance of the charge transfer process for all the PSHCs. Results exhibit PSHC-1000 electrode with the symmetry factor of 0.1352 has the smallest charge transfer resistance, leading to more easily transportation of electrons and ions. This work can provide a simple and green route for preparation of hard carbon materials derived from biomass waste with unique morphology and microstructure which can exhibit an excellent electrochemical performance.

MicroRNA (miRNA) biogenesis is finely controlled by complex layers of post-transcriptional regulators, including RNA-binding proteins (RBPs). Here, we show that an RBP, QKI5, activates the processing of primary miR-124-1 (pri-124-1) during erythropoiesis. QKI5 recognizes a distal QKI response element and recruits Microprocessor through interaction with DGCR8. Furthermore, the recruited Microprocessor is brought to pri-124-1 stem loops by a spatial RNA-RNA interaction between two complementary sequences. Thus, mutations disrupting their base-pairing affect the strength of QKI5 activation. When erythropoiesis proceeds, the concomitant decrease of QKI5 releases Microprocessor from pri-124-1 and reduces mature miR-124 levels to facilitate erythrocyte maturation. Mechanistically, miR-124 targets TAL1 and c-MYB, two transcription factors involved in normal erythropoiesis. Importantly, this QKI5-mediated regulation also gives rise to a unique miRNA signature, which is required for erythroid differentiation. Taken together, these results demonstrate the pivotal role of QKI5 in primary miRNA processing during erythropoiesis and provide new insights into how a distal element on primary transcripts affects miRNA biogenesis.

We study the large time behavior of a 3-D MHD (magneto-hydrodynamical)-type system without magnetic diffusion introduced by Lin and Zhang (2014). By using the elementary energy method and interpolation technique, we prove the global existence and decay estimate of smooth solution near the equilibrium state (x3, 0).

In this paper, we obtain the global well-posedness of non-resistive 2D MHD problem in two kinds of periodic domains: $$\mathbb T\times \mathbb R$$ and $$\mathbb T\times (0,1)$$ , without any assumption on initial data. What’s more, we find that the periodic domains have similar effects with domains with physical boundaries, although Poincare’s inequality does not hold in the zero mode.