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The evolution of body size, both within and between species, has been long 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 consistently covary with ectotherm body sizes across populations with varying local environmental conditions. Here, we used a widely distributed lizard (Eremias argus) collected from different populations situated across China to assess how climatic conditions and/or available resources at different altitudes shape the geographical patterns of lizard body size across populations. We used body size data from locations differing in altitudes across China to construct linear mixed models to test the relationship between lizard body size and ecological and climate conditions across altitudes. Lizard populations showed significant differences in body size across altitudes. Furthermore, we found that variation in body size among populations was also explained by climatic and seasonal changes along the altitudinal gradient. Specifically, body size decreased with colder and drier environmental conditions at high altitudes, resulting in a reversal of Bergmann’s rule. Limited resources at high altitudes, as measured by net primary productivity, may also constrain body size. Therefore, our study demonstrates that the intraspecific variation in female lizards’ body size may be strongly influenced by multifarious local environments as adaptive plasticity for female organisms to possibly maximise reproductive ecology along geographic clines.

The rational fabrication of heterostructures is one of efficient strategies for improving photocatalytic performance of semiconductor photocatalysts. Very recently, Domen and co-workers found that Ta3N5 single crystals grown on the surface of KTaO3 can accomplish photocatalytic overall water splitting for the first time. In order to comprehend the underlying mechanism of this photocatalytic system, we have performed a systematic study based on density functional theory first-principles calculations. Ta3N5(010)/KTaO3(110) slab models have been built according to experimental observations by considering two common terminations of KTaO3(110) surface, named as Ta3N5/O2 and Ta3N5/KTaO. The formations of interfacial bonds are thermodynamically stable, showing a covalent interaction between two components of a heterostructure. Ta3N5/O2 has a higher mobility of photogenerated charge carriers and lower recombination rate of charge carriers than Ta3N5/KTaO. The light absorption of heterostructures displays the feature of KTaO3 in the short wavelength region and the characteristic of Ta3N5 in the long wavelength region. The calculated band offsets show that Ta3N5/O2 and Ta3N5/KTaO have distinct Type-II band alignments, with Ta3N5 as the accumulator of photoinduced electrons in the former and the collector of photogenerated holes in the latter, respectively. The difference in charge density and electrostatic potential between two components acts as a driving force to promote the transfer of electrons and holes to different domains of the interface, which is beneficial to extend the lifetime of photoinduced carriers. Our results demonstrate that the function of Ta3N5 in Ta3N5/KTaO3 photocatalytic system is determined by the termination property of KTaO3(110) surface, which provides a likely reason of the observed photocatalytic activity of overall water splitting achieved by Ta3N5 synthesized by using KTaO3 as a precursor for the nitridation reaction.

Ion Mobility Spectroscopy (IMS) is commonly used for in-situ rapid online detection of trace substances at atmospheric pressure. By selecting four types of Phthalic acid Ester (PAE) compounds as the quantitative research objects, studying the effects of the temperature of the mobility tube, the temperature of the sample desorbed heater and the electric field strength of the mobility region on the detection, analysing the microscopic process of ion reaction after the addition of reagent molecules using the Rectilinear Ion Trap Mass Spectrometer (RIT-MS), the paper preliminary studies the product ions of phthalic acid ester, and establish a method for rapid measurement of phthalic acid ester-like environmental hormones with ion mobility spectrometry. With the addition of ammonia reagent molecules, the detection limits of dimethyl phthalate, diethyl phthalate, dibutyl phthalate and butyl benzyl phthalate were 0.08 and 0.1, 0.09, 0.70 ng, respectively, and relative standard deviation RSD of 6 parallel measurements

When the dimensionality of layered compounds decreases to the physical limit, ultimate two-dimensional (2D) anisotropy and/or quantum confinement effects may lead to extraordinary physicochemical attributes. Here, we report single-layer Rh nanosheets (NSs) exhibiting ultrahigh peroxidase-like activity, far exceeding that of horseradish peroxidase (HRP) and of most known layered nanomaterial-based peroxidase mimics. Considering per NS as an active subunit, the Rh NSs displayed a catalytic rate constant (Kcat) as high as 4.45 × 105 s–1 to H2O2, two orders of magnitude higher than those of HRP and Rh nanoparticles. The high atom efficiency of the Rh NSs can be attributed to the full exposure of surface-active Rh atoms, which greatly facilitates electron transfer and formation of superoxide anions, representing reactive oxygen species in the catalytic process. As a proof-of-concept application, the Rh NSs were successfully used as peroxidase mimics for the colorimetric detection of H2O2 and xanthine, with high sensitivity and selectivity. Moreover, a simple, rapid, and sensitive Rh-based paper sensor for ascorbic acid was also developed. In summary, this work provides a novel example of single-layer metallic NSs for biosensing.

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.

Ion mobility spectrometry is widely used for detection of explosives in the field of airport and in the war against terror due to its satisfactory features: fast response, high sensitivity, good portability, easy operation, etc. This paper introduced the pricinple, classification and also their features of ion mobility sepctrometry; also mainly introduced recent developments of technique for detection of explosives in our laboratory including titration region-ion mobility spectrometry, new method to improve the resolution of ion mobility spectrometry and also the nonradioactive high-efficency ionization source based on VUV lamp. Finally, the development tendency and prospect of ion mobility spectrometry for detection of explosives was predicted.

Sensitive detection of black powder (BP) by stand-alone ion mobility spectrometry (IMS) is full of challenges. In conventional air-based IMS, overlap between the reactant ion O2(-)(H2O)n peak and the sulfur ion peak occurs severely; and common doping methods, providing alternative reactant ion Cl(-)(H2O)n, would hinder the formation of ionic sulfur allotropes. In this work, an ion mobility spectrometer embedded with a titration region (TR-IMS) downstream from the ionization region was developed for selective and sensitive detection of sulfur in BP with CH2Cl2 as the titration reagent. Sulfur ions were produced via reactions between sulfur molecules and O2(-)(H2O)n ions in the ionization region, and the remaining O2(-)(H2O)n ions that entered the titration region were converted to Cl(-)(H2O)n ions, which avoided the peak overlap as well as the negative effect of CH2Cl2 on sulfur ions. The limit of detection for sulfur was measured to be 5 pg. Furthermore, it was demonstrated that this TR-IMS was qualified for detecting less than 5 ng of BP and other nitro-organic explosives.

Using citric acid as reducing agent and fuel, nitrate as a oxidant, boric acid as a flux material, red persistent phosphors CaTiO3: Pr3+, Al3+ have been successfully synthesized by nitrate-citric acid combustion method. The best route is determined by studying influences of the amount of citric acid and ammonium nitrate, pH value of the solution, initiating temperature of furnace, and the amount of boric acid. The photoluminescence and crystallinity of persistent phosphors were investigated by using luminescence spectrometer and X-ray diffractometer (XRD), respectively. The results show that the optimum molar ratio of citric acid to calcium nitrate was about 0.8 and that of boric acid to calcium nitrate was about 0.4. Photoluminescence and decay curves show that the samples exhibited the optimal luminous properties at pH value of 6 and at the initiating temperature of 700 °C.

We determined the complete mitochondrial genome of Kaloula rugifera in 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 except ND1 gene beginning with GTG and COI gene beginning with ATA. Five protein-coding genes (COII, ATP 6, COIII, ND3 and ND4) 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.

The complete mitochondrial genome of the Oreolalax lichuanensis was determined. It is a circular molecule of 17 702 bp in size and consists of 13 protein-coding genes, 23 tRNA genes, two rRNA genes and a control region (D-loop). The base composition on light strand was 28.0% A, 32.2% T, 24.9% C and 14.9% G. Compared with most other vertebrates, this mitogenome appear a tandem duplication of tRNA-Met gene. This study will facilitate the further research of the population genetics of this species and systematic study of the genus Oreolalax.

The complete mitogenome of Leishan moustache toad, Vibrissaphora leishanensis, is determined. The mitogenome size is 17,485 bp, containing 13 protein-coding genes, 2 rRNA genes, 23 tRNA genes and a control region (D-loop). The base composition of the whole genome is 28.1% A, 32.6% T, 24.4% C and 14.8% G. As observed in this genus before, this mitogenome also appears a tandem duplication of tRNAMet gene. This study will provide fundamental data for further research to resolve population genetics of this species and systematic problems of the genus Vibrissaphora.

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 (ΔGo mic). 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 (Гmax, Amin and ∆Go mic) 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.

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 O 2 − ( H 2 O ) n in the drift region so as to avoid the overlap between O 2 − ( H 2 O ) n 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 1.4 ppm CCl4 as the modifier, the minimum detectable quantity of 0.1 ng 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.

A nano-electrospray ionization-ion mobility spectrometer (nanoESI-IMS) was built up. Firstly, the effects of the parameters such as drift gas flow rate and solvent flow rate on the desolvation capability were studied and optimized. Then, a series of compounds were used to characterize the nanoESI-IMS system. The results showed that, complete desolvation was achieved for nano-electrospray ion droplets with the nanoESI-IMS apparatus. The limit of detection of this instrument for trioctylamine could reach 10 microg/L. Finally, this instrument was coupled to the high performance liquid chromatography (HPLC) as a detector for amines analysis. A test mixture containing triethylamine, diethylamine and butylamine was successfully separated and determined by the HPLC-nanoESI-IMS system. Linear response ranges of about two orders of magnitude were achieved for triethylamine, diethylamine and butylamine with this system.

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.