Biological effects induced by swift heavy ions of lithium on aqueous solution of plasmid pMTa4

Biological samples exposed to swift heavy ions sustain damage on different components. Damage to DNA, a critical component of a living system, has considerable biological implications. In this study aqueous solution of plasmid pMTa4 was exposed to varying fluence of swift ⁷Li ions and its different topological forms were analysed by agarose gel electrophoresis to study the induced damage. To monitor radiation labile nucleotide sequence the ⁷Li ions exposed plasmid was degraded by three different restriction endonucleases and also analysed by agarose gel electrophoresis. The results show that ⁷Li ions predominantly induced double strand breaks in the plasmid DNA in a dose-dependent manner and affected preferentially the GC-rich motifs of the DNA. The results suggest that ⁷Li ions induce premutagenic lesions at an enhanced frequency in segments of the DNA which are rich in CG content as compared to GC-poor segments.     

Density functional theory calculations of photophysical properties of linear 2, 7-carbazole derivatives as solar cell materials

A theoretical study has been performed to explore the optical and electronic properties on a series of linear 2, 7-carbazole derivative (PCDTBT) by introducing vinyl (v) as linkage and/or benzene (B) as end-capped group for solar cell materials. The PBE0/6-31G(d) method was employed to calculate the frontier molecular orbital (FMO) and energy gap of all derivatives. The values of energy gap change less than 0.28?eV depending on v as linkage and/or B as end-capped group. The absorption spectra was evaluated using the TD-PBE0/6-31?+?G(d,p) level on the basis of the optimized geometries. The absorption spectrum has a red shift along with the increasing of molecular chain. The results of ionization potential (IP), electron affinity (EA), and reorganization energy (λ) reveal that, v as linkage and/or B as end-capped group both lead to the increase of charger transfer rates for PCDTBT. Moreover, v as linkage and/or B as end-capped group have slight effects on the stability property of PCDTBT.     

Towards an easy carbon dioxide reduction in aqueous solution

Abstract

The homogeneous hydrogenation of carbon dioxide into formate anion has been investigated in aqueous solution, using water soluble ruthenium(1I)-phosphine (meta-monosulphonated triphenylphosphine, TPPMS; and 1,3,5-triaza-7-phosphaadamantane, PTA) complexes as catalysts. These reactions take place in amine free medium under mild conditions, bicarbonate anion is more active than carbon dioxide in the reduction. The initial turnover frequenc of the reduction increases with increasing H₂ pressure, as it was observed in situ by C and 'H NMR spectroscopy. High pressure FT-IR were used to find evidence for the formation of the catalytically active ruthenium hydride species.     

Synthesis of a Cationic Polymer-Bentonite Composite Utilizing a Simple and Green Process for the Adsorption of Acid Orange 7 from Aqueous Solution

A one-step, green process is reported for synthesis of poly([2-(methacryloyloxy)ethyl] trimethylammonium chloride) (PMETAC) modified bentonite (Bent-PMETAC). The Bent-PMETAC was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Zeta potential, scanning electron microscopy (SEM) and thermal gravimetric analysis (TGA). The results indicated that large amounts of PMETAC were successfully grafted on the surface and interlayers of bentonite, and changed the Zeta potential of the sample from negative to positive. Acid Orange 7 (AO 7), as adsorbate, was used to test the anionic dye adsorption of the samples. The batch adsorption results implied that this novel Bent-PMETAC adsorbent exhibited a much higher removal (95%) of AO 7 than bentonite (10%). In addition, the adsorption process was hardly influenced by pH, which is in good agreement with the results of the Zeta potential analysis. The equilibrium adsorption isotherms and the adsorption kinetics of AO 7 fitted well to the Langmuir model and pseudo-second-order kinetic model, respectively. The maximum adsorption capacity of AO 7 onto Bent-PMETAC was 208.6?mg·g^?1 at 298?K, which is much higher than for most other materials. Overall, the results indicated the Bent-PMETAC is a low-cost, simple synthesis and highly efficient adsorbent for anionic dye removal from aqueous solutions.     

高效液相色谱/质谱法测定4个玉米品种幼苗中丁布含量

丁布是植物中一种重要的组成型抗菌、抗虫活性物质。采用HPLC和HPLCMS方法对我国主栽的农大80、农大108、农大115和农大368等4个玉米品种幼苗中的丁布进行了定性和定量研究。结果证实,供试的4个玉米品种培育7d的正常幼苗和黄化幼苗中均含有丁布;不同品种之间丁布含量具有显著差异,由高到低依次为农大368>农大80>农大108>农大115,其中农大368整株正常幼苗和黄化幼苗中丁布含量分别达到0.441和1.220mg/fwg,而农大115整株正常幼苗和黄化幼苗中丁布含量仅分别为0.111和0.314mg/fwg;供试玉米品种的黄化幼苗整株和地上部中的丁布含量分别显著高于对应品种的正常幼苗整株和地上部中丁布的含量,提高幅度分别为74.0%～182.9%和19.7%～40.7%;正常幼苗和黄化幼苗地上部中丁布的含量明显高于其根部。综合分析认为,供试的4个玉米品种中农大368的黄化幼苗地上部器官是提取丁布的优选材料。     

Anodic composite deposition of RuO2·xH2O–TiO2 for electrochemical supercapacitors

This communication demonstrates the first work on anodic composite deposition of oxide nanocomposites. Rutile TiO₂ nanoflowers with an average petal size of ca. 10 nm in diameter and 100 nm in length were synthesized from a TiCl₃ solution purged with air at 25 °C for 12 days prior to the composite deposition. Hydrous ruthenium oxide (RuO₂·xH₂O) and TiO₂ nanoflowers were composite-deposited onto Ti substrates for supercapacitors. In comparing with RuO₂·xH₂O deposits, RuO₂·xH₂O–TiO₂ nanocomposites with a highly porous nature exhibit the weakly mass-dependent specific capacitance and high-power capacitive characteristics.     

Effects of variation in modulator temperature during cryogenic modulation in comprehensive two‐dimensional gas chromatography

Many modulation systems in comprehensive 2D GC (GC×GC) are based on cryogenic methods. High trapping temperatures in these systems can result in ineffective trapping of the more volatile compounds, whilst temperatures that are too low can prevent efficient remobilisation of some compounds. To better understand the trapping and release of compounds over a wide range of volatilities, we have investigated a number of different constant temperature modulator settings, and have also examined a constant temperature differential between the cryo‐trap and the chromatographic oven. These investigations have led us to modify the temperature regulation capabilities of the longitudinally modulated cryogenic system (LMCS). In contrast to the current system, where the user sets a constant temperature for the cooling chamber, the user now sets the temperature difference between the cryo‐trap and the chromatographic oven. In this configuration, the cooling chamber temperature increases during the chromatographic run, tracking the oven temperature ramp. This produces more efficient, volatility‐dependent modulation, and increases the range of volatile compounds that can be analysed under optimal trap‐and‐release conditions within a single analytical run. This system also reduces cryogenic fluid consumption.     

Sensitivity analysis for a system of parametric general quasi-variational-like inequality problems in uniformly smooth Banach spaces

In this paper, using the concept of P-η-proximal-point mapping introduced by Kazmi and Bhat [11], we study the existence and sensitivity analysis of the solution set of a system of parametric general quasi-variational-like inequality problems in uniformly smooth Banach spaces. Further under suitable conditions, we discuss the Lipschitz continuity of the solution set with respect to the parameters. The approach used in this paper may be treated as an extension and unification of approaches for studying sensitivity analysis for various important classes of variational inequalities given in [1,2,4,12,14–16,21–24].