Spatiotemporal dynamics induced by nonlocal competition in a diffusive predator-prey system with habitat complexity

Nonlinear Dynamics - In this paper, we study a delayed diffusive predator–prey model with nonlocal competition in prey and habitat complexity. The local stability of coexisting equilibrium is...     

Remarks on the a priori bound for the vorticity of the axisymmetric Navier-Stokes equations

Applications of Mathematics - We study the axisymmetric Navier-Stokes equations. In 2010, Loftus-Zhang used a refined test function and re-scaling scheme, and showed that $$\left| {{\omega...     

Determination of relative binding affinities of labeling molecules with amino acids by using scanning tunneling microscopy

The binding behaviour of labeling molecule copper phthalocyanine tetrasulfonate sodium (PcCu(SO(3)Na)(4)) on the assemblies of representative polyamino acids has been studied by using scanning tunneling microscopy (STM). By directly visualizing the adsorption and distribution of the labeling species on the peptide assemblies in STM images, one could obtain relative binding affinities of the labeling molecule with different amino acid residues.     

GO-PtNi hybrid nanoenzyme mimics for the colorimetric detection of hydrogen peroxide

GO-PtNi nanocomposites with intrinsic peroxidase-like activity were obtained through one-pot synthesis. The hybrid nanomaterial was characterized by transmission electron microscopy (TEM) and X-ray powder diffraction (XRD). The peroxidase-like activity of GO-PtNi nanocomposites was found to be dependent on pH, temperature, the concentration of enzyme and substrates. The optimal conditions for the catalytic activity of GO-PtNi nanocomposites were determined. Based on these findings, a simple and sensitive colorimetric method for the detection of H₂O₂ by using GO-PtNi nanocomposites and 3,3′,5,5′-tetramethylbenzidine (TMB) was developed. The linear range was from 0.08 to 1.5 mM with a detection limit of 5 μM.     

合金铸铁的X射线荧光光谱分析

探讨了用ＸＲＦ法测定合金铸铁中Ｓi、Mn、P、S、Ni、Cr、Cu、Al、Mo、V、T、Nb、Sn、W、Co１５个杂质元素的分析方法，简述了分析条件及实验方法，方法简便、快速、准确、精密度较好。     

Peptide-tailored assembling of Au nanorods

By investigating the influence of peptides on the assembling process of Au nanorods induced by 4-mercaptopyridine, two kinds of peptides were identified. The nature of peptides plays an important role in tailoring assembling, which makes potential peptide recognition and detection possible.     

Solution-processable porous graphitic carbon from bottom-up synthesis and low-temperature graphitization

It is urgently desired yet challenging to synthesize porous graphitic carbon (PGC) in a bottom-up manner while circumventing the need for high-temperature pyrolysis. Here we present an effective and scalable strategy to synthesize PGC through acid-mediated aldol triple condensation followed by low-temperature graphitization. The deliberate structural design enables its graphitization in situ in solution and at low pyrolysis temperature. The resulting material features ultramicroporosity characterized by a sharp pore size distribution. In addition, the pristine homogeneous composition of the reaction mixture allows for solution-processability of the material for further characterization and applications. Thin films of this PGC exhibit several orders of magnitude higher electrical conductivity compared to analogous control materials that are carbonized at the same temperatures. The integration of low-temperature graphitization and solution-processability not only allows for an energy-efficient method for the production and fabrication of PGC, but also paves the way for its wider employment in applications such as electrocatalysis, sensing, and energy storage.

Porous graphitic carbon was synthesized through acid-mediated aldol triple condensation followed by low-temperature graphitization. The inherent thin film processability and the low temperature requirement of the synthesis enable various potential applications.     

分散液液微萃取–高效液相色谱法测定尿液中的阿替洛尔

建立基于离子液体–分散液液微萃取–高效液相色谱法检测尿液中阿替洛尔的新型分析方法.将环境友好的萃取剂离子液体和分散剂乙腈的混合溶液快速注入样品中,瞬间完成高效的萃取过程.在低温条件下,将下层的离子液体固化,实现萃取剂高效地收集,用高效液相色谱–二极管阵列检测器进行定量分析.阿替洛尔的质量浓度在0.01～1μg/mL范围...     

Co-assembly of human islet amyloid polypeptide (hIAPP)/insulin

The pathogenesis of type II diabetes can be linked to cosecreted hIAPP/insulin interacting with cell membranes. Here we investigate the nanostructures by co-assembling hIAPP and insulin on surfaces. By tuning the hIAPP/insulin ratio, atomic force microscopy reveals the resulting nanostructure morphology changes from fibrils to oligomers, to annular. Implications for in vivo studies are discussed.     

Liquid Crystals Anchored on Mixed Monolayers of Chiral versus Achiral Molecules: Continuous Change in Orientation as a Function of Enantiomeric Excess

The orientations of liquid crystals (LCs) anchored on monolayers formed from mixtures of chiral versus achiral molecules were compared. Changes in the enantiomeric excess of mixed monolayers of chiral dipeptides gave rise to continuous changes in the orientations of nematic LCs, allowing arbitrary tuning of the azimuthal orientations of LCs over a range of ≈100°. In contrast, the same LCs exhibited discontinuous changes in orientation on surfaces presenting mixtures of achiral molecules. These striking differences in the anchoring of LCs on surfaces presenting chiral versus achiral molecules provide insights into the molecular origins of ordering transitions of LCs, and provide new principles based on chiral monolayers for the rational design of surfaces that permit continuous tuning of the orientations of LCs.