Silver nanoparticles (NPs) were rapidly synthesized by treating silver ions with a Capsicum annuum L. extract. The reaction process was simple and convenient to handle, and was monitored using ultraviolet-visible spectroscopy (UV-vis). The effect of Capsicum annuum L. proteins on the formation of silver NPs was investigated using X-ray photoemission spectroscopy (XPS), electrochemical measurements, Fourier-transform infrared spectroscopy (FTIR) and differential spectrum techniques. The morphology and crystalline phase of the NPs were determined from transmission electron microscopy (TEM), selected area electron diffraction (SAED) and X-ray diffraction (XRD) spectra. The results indicated that the proteins, which have amine groups, played a reducing and controlling role during the formation of silver NPs in the solutions, and that the secondary structure of the proteins changed after reaction with silver ions. The crystalline phase of the NPs changed from polycrystalline to single crystalline and increased in size with increasing reaction time. A recognition-reduction-limited nucleation and growth model was suggested to explain the possible formation mechanism of silver NPs in Capsicum annuum L. extract.

Potassium ion-batteries (PIBs) have attracted tremendous attention recently due to the abundance of potassium resources and the low standard electrode potential of potassium. Particularly, the solid-electrolyte interphase (SEI) in the anode of PIBs plays a vital role in battery security and battery cycling performance due to the highly reactive potassium. However, the SEI in the anode for PIBs with traditional electrolytes is mainly composed of organic compositions, which are highly reactive with air and water, resulting in inferior cycle performance and safety hazards. Herein, a highly stable and effective inorganic SEI layer in the anode is formed with optimized electrolyte. As expected, the PIBs exhibit an ultralong cycle performance over 14 000 cycles at 2000 mA g and an ultrahigh average coulombic efficiency over 99.9%.

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Chiral nanophotonic materials are promising candidates for biosensing applications because they focus light into nanometer dimensions, increasing their sensitivity to the molecular signatures of their surroundings. Recent advances in nanomaterial-enhanced chirality sensing provide detection limits as low as attomolar concentrations (10–18 M) for biomolecules and are relevant to the pharmaceutical industry, forensic drug testing, and medical applications that require high sensitivity. Here, we review the development of chiral nanomaterials and their application for detecting biomolecules, supramolecular structures, and other environmental stimuli. We discuss superchiral near-field generation in both dielectric and plasmonic metamaterials that are composed of chiral or achiral nanostructure arrays. These materials are also applicable for enhancing chiroptical signals from biomolecules. We review the plasmon-coupled circular dichroism mechanism observed for plasmonic nanoparticles and discuss how hotspot-enhanced plasmon-coupled circular dichroism applies to biosensing. We then review single-particle spectroscopic methods for achieving the ultimate goal of single-molecule chirality sensing. Finally, we discuss future outlooks of nanophotonic chiral systems.

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Via incorporation of Sr2+ into (Pb,La)(Zr,Sn,Ti)O3, high recoverable energy density (Ure) is achieved in (Pb,Sr,La)(Zr,Sn,Ti)O3 (PSLZST) ceramics. All Sr2+ modified ceramics exhibit orthorhombic antiferroelectric (AFE) characteristics, and have higher ferroelectric-AFE phase switching electric field (EA, proportional to Ure) than the base composition with a tetragonal AFE phase. By properly adjusting the Sr2+ content, the Ure of PSLZST ceramics is greatly improved. This is attributed to the substitution of Pb2+ by Sr2+ with a smaller ion radius, which decreases the tolerance factor leading to enhanced AFE phase stability and thus increased EA. The best energy storage properties are achieved in the PSLZST ceramic with a Sr2+ content of 0.015. It exhibits a maximum room-temperature Ure of 5.56 J/cm3, the highest value achieved so far for dielectric ceramics prepared by a conventional sintering technique, and very small energy density variation (<12%) in the range of 30–90 °C. The high Ure (>4.9 J/cm3) over a wide temperature range implies attractive prospects of this material for developing high power capacitors usable under various conditions.

Parasitic flatworms of the genus Schistosoma are the causative agents of schistosomiasis, which afflicts more than 200 million people yearly in tropical regions of South America, Asia and Africa. A promising approach to the control of this and many other diseases involves the application of our understanding of small non-coding RNA function to the design of safe and effective means of treatment. In a previous study, we identified five conserved miRNAs from the adult stage of Schistosoma japonicum. Here, we applied Illumina Solexa high-throughput sequencing methods (deep sequencing) to investigate the small RNAs expressed in S. japonicum schistosomulum (3 weeks post-infection). This has allowed us to examine over four million sequence reads including both frequently and infrequently represented members of the RNA population. Thus we have identified 20 conserved miRNA families that have orthologs in well-studied model organisms and 16 miRNA that appear to be specific to Schistosoma. We have also observed minor amounts of heterogeneity in both 3′ and 5′ terminal positions of some miRNA as well as RNA fragments resulting from the processing of miRNA precursor. An investigation of the genomic arrangement of the 36 identified miRNA revealed that seven were tightly linked in two clusters. We also identified members of the small RNA population whose structure indicates that they are part of an endogenously derived RNA silencing pathway, as evidenced by their extensive complementarities with retrotransposon and retrovirus-related Pol polyprotein from transposon.