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The evolution of body size within and among species is predicted to be influenced by multifarious environmental factors. However, the specific drivers of body size variation have remained difficult to understand because of the wide range of proximate factors that covary with ectotherm body sizes across populations with varying local environmental conditions. Here, we used female Eremias argus lizards collected from different populations across their wide range in China, and constructed linear mixed models to assess how climatic conditions and/or available resources at different altitudes shape the geographical patterns of lizard body size across altitude. Lizard populations showed significant differences in body size across altitudes. Furthermore, we found that climatic and seasonal changes along the altitudinal gradient also explained variations in body size among populations. Specifically, body size decreased with colder and drier environmental conditions at high altitudes, reversing Bergmann's rule. Limited resources at high altitudes, measured by the low vegetative index, may also constrain body size. Therefore, our study demonstrates that multifarious environmental factors could strongly influence the intraspecific variation in organisms' body size. [ABSTRACT FROM AUTHOR]

Abstract: This paper introduces a simple method for selective and sensitive detection of black powder by adding chlorinated hydrocarbons in the drift gas instead of changing the structure of conventional ion mobility spectrometer (IMS). The function of chloride modifiers was to substitute Cl−(H2O) n for in the drift region so as to avoid the overlap between and sulfur ion peaks. Among CH2Cl2, CHCl3 and CCl4, CCl4 was chosen as the modifier due to the best peak-to-peak resolution and stability towards the fluctuation of modifier concentration. With 1.4ppm CCl4 as the modifier, the minimum detectable quantity of 0.1ng for sulfur was achieved. Moreover, this method showed the ability for detection of common explosives at sub-nanogram level, such as black powder (BP), ammonium nitrate fuel oil (ANFO), 2,4,6-trinitrotoluene (TNT), and pentaerythritol tetranitrate (PETN). In summary, this method requiring no configuration modification has high sensitivity and selectivity, and consumes trace amount of modifier. And these characteristics make it easy to be adopted in current deployed IMS to detect black powder explosives. [Copyright &y& Elsevier]

This study investigates the photocatalytic reduction of nitroaromatic compounds upon visible light over novel Ce-doped UiO-66/graphene nanocomposites. Ce doped UiO-66 nanostructures and the corresponding graphene hybridized nanocomposites were facilely synthesized by means of one step solvothermal reaction. It has been demonstrated that produced nanocomposites could be used as highly efficient and chemical stable photocatalysts for the reduction of nitroaromatic compounds under visible irradiation and ambient conditions. Compared with the bare UiO-66, Ce-UiO-66/GR distinctly enhanced photocatalytic activity. Ce as “ mediator ” introduced into the MOFs materials can greatly improve the electron transfer across the interface between grephene and the UiO-66 and further improve the visible light driven photoactivity. This is an effective strategy for the development of high photocatalytic activity MOFs based materials. [ABSTRACT FROM AUTHOR]

Photocatalytic synthesis using visible light is a desirable chemical process because of its potential to utilize sunlight. A heterostructured MIL-125/Ag/g-C 3 N 4 nanocomposite was implemented as an efficient bifunctional visible-light response catalyst for the photoreduction of nitrocompounds and the oxidation of alcohols. The photocatalyst was prepared via an accessible method and characterized by XRD, SEM, TEM, XPS, FT-IR, N 2 adsorption–desorption isotherm, UV–vis DRS, PL and EIS. The reactive efficiency of the photocatalyst depends on two primary factors, one is the light adsorption of catalysts, Ag nanoparticles (NPs) were photodeposited on the surface of g-C 3 N 4 and MIL-125 to increase visible-light absorption via the surface plasmon resonance. And the other is the separation efficiency of the photogenerated charge carrier. As an electron-conduction bridge in the interface between MIL-125 and g-C 3 N 4 , Ag NPs could facilitate the direct migration of photoinduced electrons from g-C 3 N 4 to MIL-125 and retard the recombination of electron-holes. Therefore, the MIL-125/Ag/g-C 3 N 4 sample shows highest photocatalytic activity compared with MIL-125, g-C 3 N 4 , MIL-125/Ag and MIL-125/g-C 3 N 4 . A corresponding photocatalytic mechanism of these reactions was discussed in detail. Moreover, the photoreduction of nitrocompounds and oxidation of the alcohols with superior conversions and selectivities were obtained, and the catalyst can be recycled four times. It is concluded that MIL-125/Ag/g-C 3 N 4 would be a promising visible light photocatalyst in the field of selective organic transformations. [ABSTRACT FROM AUTHOR]

A series of MIL-53(Fe)-graphene nanocomposite photocatalysts were synthesized by a facile one-pot solvothermal reaction. All materials have been thoroughly characterized by FT-IR, SEM, TEM, PXRD, UV–vis DRS and PL analysis. It was demonstrated that the introducing of graphene on the MIL-53(Fe) would minimize the recombination of photogenerated electron-hole pairs, thus, leading to the enhancement of photocatalytic activity. MIL-53(Fe)-graphene nanocomposite was an efficient catalyst towards the photocatalytic selectively oxidation of alcohols to the corresponding aldehydes or ketones under visible light and ambient conditions. High selectivity of the aldehydes or ketones (99%) were obtained. Meanwhile, the catalyst can be recycled at least four times without loss of catalytic efficiency. A possible photocatalytic reaction mechanism involving a direct photogenerated hole-oxidation process was also investigated in detail by the active species trapping experiments and the related electrochemical analysis. [ABSTRACT FROM AUTHOR]

The development of highly active and low-cost electrocatalysts with excellent durability is a major challenge for glucose catalysis. Here, we report a fast and low-cost electrodeposition method for preparing a new NiCuO flower-like nanostructure with non-noble metals. The new NiCuO catalyst shows significant efficiency for glucose electrooxidation, which reaches an oxidative peak mass activity of 376.80 A g−1 and retains 66% of the original current over 10,000 s in a stability test by chronoamperometry. We credit the excellent glucose oxidation activity and outstanding stability to the combination of non-noble metal materials and the flower-like nanostructures of the NiCuO/ITO electrode, which results in large electrochemically active surface areas (ECSAs) of 85.9 m2 g−1 and fast charge transfer as measured by electrochemical impedance spectroscopy (EIS). This new NiCuO nanoflower catalyst provides a new functional material for the building of glucose fuel cells and other electrochemical devices. [Display omitted] • NiCuO/ITO electrode was prepared by sequential electrodeposition. • Deposition of Cu for only 2 CV cycles led to enhanced glucose electrooxidation. • The NiCuO/ITO had large ECSAs, high mass activity, and long-term stability. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome of a stream-dwelling frog species Paramegophrys oshanensis was determined. This mitogenome was 17,747 bp in length, containing 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and a control region (D-loop). The base composition of the light strand was 28.77% A, 29.85% T, 26.26% C, and 15.11% G. Compared with most other vertebrates, this mitogenome has some different features: a non-tandem duplication of tRNA-Met gene (forming tRNA-Met1 and tRNA-Met2 genes), the replacement of tRNA-Trp gene by a 72-bp noncoding region translocated from the cluster of WANCY to the back of Cytb gene, the translocation of tRNA-Val gene from the front of 16S rRNA to the back of tRNA-Met1 gene, and the translocation of tRNA-Pro gene from the front of D-loop region to the front of tRNA-Met2 gene. Three kinds of tandem repeats with size ranging from 71 to 92 bp were detected within D-loop region. [ABSTRACT FROM AUTHOR]

We determined the complete mitochondrial genome ofKaloula rugiferain this work. The mitogenome was 17,073 bp in length, containing 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a control region (D-loop). The base composition of the light strand was 29.7% A, 30.4% T, 25.7% C and 14.2% G. The gene order and contents of it is identical to most amphibian mitogenome. All protein-coding genes began with ATG as start codon exceptND1gene beginning with GTG andCOIgene beginning with ATA. Five protein-coding genes (COII, ATP 6, COIII, ND3andND4) ended with incomplete stop codon T. The 22 tRNA genes with the size ranging from 65 bp to 73 bp were interspersed along the whole genome. The D-loop region containing tandem repetition was 1675 bp in length and heavily biased to A + T nucleotides. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs), a new class of porous crystalline materials, have attracted great interest as fascinating applications for eco-friendly photocatalysts. In this study, new hybrid MOFs, iron doped zirconium based metal-organic frameworks, FeUiO-66, were successfully synthesized by hydrothermal method firstly. Then the PANI/FeUiO-66 nanohybrids were fabricated through annealing process. The photocatalytic performances of the obtained PANI/FeUiO-66 nanohybrids were evaluated by selectively oxidation of various alcohol substrates using molecular oxygen as a benign oxidant. Boosting by synergistically multi-doped effect, the catalytic activity of the novel PANI/FeUiO-66 is remarkably higher than that of bare UiO-66 under visible light irradiation at ambient temperature. Further analyses revealed that the enhancement of photocatalytic activity originated from the two aspects. On one hand, when the Fe doped into the framework, valence fluctuation of Fe 2+ /Fe 3+ could reduce the recombination rate of photoexcited carriers. On the other hand, based on energy band matching between FeUiO-66 and PANI, the easily formed heterostructures from PANI and FeUiO-66 can efficiently enhance the separation of photogenerated carriers. Furthermore, by virtue of unique advantage of the position of the CB and VB of FeUiO-66, alcohols could be selectively oxidized by the O 2 − and h + . Remarkably, it is expected that the MOF-conductive conjugated polymers nanohybrids could be used as efficient visible light driven photocatalysts for organic transformation with high selectivity under eco-friendly conditions. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNTs) supported HSiW/MWCNTs was successfully prepared and characterized by Fourier transform infrared spectoscopy, X-ray powder diffraction, transmission electron microscopy and N adsorption-desorption test. Its catalytic performance for the catalytic Baeyer-Villiger oxidation of cyclic ketones with 30 % HO as oxidants was investigated. It was found that HSiW/MWCNTs was very efficient to transform of some cycloketones to the corresponding lactones with high conversions as well as selectivities. Factors affecting the oxidations and the reusability of the catalyst were also investigated. It was found that the catalyst can be reused seven times in the catalytic oxidation reaction of cyclopentanone without obviously catalytic activity losing in the oxidation. Graphical Abstract: A supported solid acid of HSiW/MWCNTs was used as efficient catalyst for the Baeyer-Villiger oxidation of ketones. High cyclopentanone conversion (98 %) and ε- valerolactone selectivity (99 %) were obtained. The catalyst can be reused at least seven runs in the oxidation of cyclopentanone.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Ion mobility spectrometry (IMS) was explored in the selective detection of nitrobenzene compounds in industrial waste water and surface water, and the selectivity was theoretically elucidated with the transformation energy in the product ion formation reaction. A linear detection range of 0.5–50 ppm and a limit of detection (LOD) of 0.1 ppm were found for 2,4,6-trinitrotoluene (TNT). With the IMS as the detection system of molecularly imprinted polymer (MIP) separation technique, the MIP-IMS system was proved to be excellent method to detect trace amount of nitrobenzene compounds in surface water, in which more than 87% of nitrobenzene compounds could be adsorbed on MIPs with 90–105% of recovery. [ABSTRACT FROM AUTHOR]

An amphipathic highly branched diblock polyether, PA60-2-40, was synthesized via anion ring-opening polymerization of propylene oxide (PO) and ethylene oxide (EO), using phenol-amine resin (PA) as the initiator. The molecular structure was confirmed by FT-IR and 1H NMR. The surface tension and fluorescence spectroscopy measurements provide information about the effect of cosolvents on the critical micelle concentration (CMC) and the standard Gibbs energy (ΔG omic). The cosolvents have a significant effect on the CMC of PA60-2-40; the CMC first decreases and then increases with increasing content of n-pentanol, but with an increase of ethylene glycol concentration, there is durative decrease of the CMC. The micellization becomes more spontaneous in the presence of cosolvents with more hydroxyl groups, but the CMC does not monotonically increase or decrease with the increasing carbon chain length of aliphatic monohydric alcohols. The values of surface activity parameters (Г max, A min and ∆G omic) calculated all coincide with the results of the experiment. Additionally, TEM and DLS demonstrate that the size of the micelles can be changed by the addition of alcohols, but the aggregation morphology will not change. [ABSTRACT FROM AUTHOR]