Catalyst size dependent growth of Pd-catalyzed one-dimensional InAs nanostructures

In this study, Pd was used as catalyst to grow one-dimensional InAs nanostructures on GaAs (111)(B) substrates in order to explore the growth mechanism and the effect of non-gold catalysts in growing epitaxial III-V nanostructures. With detailed morphological, structural, and chemical characterizations using electron microscopy, coupled with analysis of the Pd-In binary phase diagram, it was found that size of Pd nanoparticles plays a key role in determining the growth mechanism of one-dimensional InAs nanostructures. (C) 2013 AIP Publishing LLC

Ion-exchange voltammetry at polymer film-coated nanoelectrode ensembles.

Ensembles of nanoscopic disk-shaped electrodes have been shown to offer enhancements in electroanalytical detection limits relative to electrodes of macroscopic dimensions (e.g., disk electrodes with diameters of 1 mm). Enhancements in electroanalytical detection limits have also been observed at macroscopic electrodes that have been coated with films of ion-exchange polymers. In this paper we combine these two concepts. We demonstrate that a nanoelectrode ensemble (NEE) that has been coated with a thin film of the Kodak ion-exchange polymer AQ 55 shows enhanced electroanalytical detection limits relative to the uncoated NEE and to the coated macroscopic electrode. To our knowledge, this is the first investigation of the electrochemistry, and the electroanalytical advantages, of polymer film-coated NEEs

Cryptanalysis and Improvement of an Efficient and Secure Medical Image Protection Scheme

Nowadays, the increasing demand for telemedicine services has raised interest in the real-time medical image protection literatures. In this paper, we evaluate the security of an efficient and secure medical image protection scheme recently proposed (Fu et al., 2013). It is found that this scheme can be successfully broken by launching chosen-plaintext attacks. Improvement is subsequently developed for promoting the security and efficiency performance. Extensive security analyses and experimental results both indicate that the improved scheme can well address the security flaws and advance the speed performance of the original one

Correction: Computer-aided design of high-efficiency GeTe-based thermoelectric devices

Correction for ‘Computer-aided design of high-efficiency GeTe-based thermoelectric devices’ by Min Hong et al., Energy Environ. Sci., 2020, DOI: 10.1039/d0ee01004a. The authors regret errors in the author affiliations in the original manuscript. The corrected list of authors and affiliations for this paper is as shown above. The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers

The underlying microbial mechanism of epizootic rabbit enteropathy triggered by a low fiber diet

Publication history: Accepted - 24 July 2018; Published online - 21 August 2018.Epizootic rabbit enteropathy (ERE) is reproduced successfully in the present study by feeding rabbits a low-fibre diet, and high-throughput sequencing and quantitative real-time PCR (qPCR) analysis were applied to examine the microbial variations in the stomach, small intestine and caecum. The evenness was disturbed and the richness was decreased in the ERE groups. When the rabbits were suffering from ERE, the abundance of the Firmicutes was decreased in three parts of the digestive tract, whereas the Proteobacteria was increased in the stomach and caecum, the Bacteroidetes and Verrucomicrobia were increased in the small intestine. Correlation analysis showed that the reduced concentrations of TVFA and butyrate in the caeca of the ERE group were attributed to the decreased abundances of genera such as Lactobacillus, Alistipes and other fibrolytic bacteria and butyrate- producing bacteria such as Eubacterium and Faecalibacterium. It is concluded that, in terms of microorganisms, the overgrowth of Bacteroides fragilis, Clostridium perfringen, Enterobacter sakazakii and Akkermansia muciniphila and inhibition of Bifidobacterium spp. and Butyrivibrio fibrisolvens in the stomach, small intestine and caecum resulted in a decrease in butyrate yield, leading to the incidence of ERE, and the probability of developing ERE could be manipulated by adjusting the dietary fibre level.The financial support was provided by the International Cooperation Project of Ministry of Science and Technology of China (2014DFA32860)

Bi0.5Sb1.5Te3/PEDOT:PSS-based flexible thermoelectric film and device

Incorporating inorganic thermoelectric fillers into conductive polymers is one promising strategy to develop high-performance flexible thermoelectric films. However, due to the relatively high interfacial contact resistance between fillers and polymers, carriers tend to be scattered at the interfaces during the interfacial transports, which deteriorates the electrical properties of the system, and in turn leads to low energy conversion efficiency. Here, a new strategy is developed to optimize interfacial carrier transports in Bi0.5Sb1.5Te3/PEDOT:PSS composite, by coating Bi0.5Sb1.5Te3 fillers with highly conductive CuTe layer. With highly crystallized PEDOT:PSS prepared as the matrix, high-performance Cu-Bi0.5Sb1.5Te3 /PEDOT:PSS film is fabricated with promising σ of ~2300 S cm−1 and peak S2σ of 312 µW m−1 K−2 at room temperature, which reaches to a record-high value in the reported Bi0.5Sb1.5Te3/PEDOT:PSS composites. Accordingly, a home-made flexible thermoelectric device is fabricated using our prepared composites, generating a promising open-circuit thermovoltage of ~7.7 mV with the human wrist as the thermal source. This study addresses the significance of interfacial carrier transport, hinting the bright prospects of cheap conductive polymers as the effective power source of wearable electronics

Causes of differences in model and satellite tropospheric warming rates

In the early twenty-first century, satellite-derived tropospheric warming trends were generally smaller than trends estimated from a large multi-model ensemble. Because observations and coupled model simulations do not have the same phasing of natural internal variability, such decadal differences in simulated and observed warming rates invariably occur. Here we analyse global-mean tropospheric temperatures from satellites and climate model simulations to examine whether warming rate differences over the satellite era can be explained by internal climate variability alone. We find that in the last two decades of the twentieth century, differences between modelled and observed tropospheric temperature trends are broadly consistent with internal variability. Over most of the early twenty-first century, however, model tropospheric warming is substantially larger than observed; warming rate differences are generally outside the range of trends arising from internal variability. The probability that multi-decadal internal variability fully explains the asymmetry between the late twentieth and early twenty-first century results is low (between zero and about 9%). It is also unlikely that this asymmetry is due to the combined effects of internal variability and a model error in climate sensitivity. We conclude that model overestimation of tropospheric warming in the early twenty-first century is partly due to systematic deficiencies in some of the post-2000 external forcings used in the model simulations