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Two isomers, different only by bond angles, are discovered for Au2I3–, due to competition between aurophilic interactions and covalent bonding., We report a joint photoelectron spectroscopy and theoretical investigation of the gaseous Au2I3– cluster, which is found to exhibit two types of isomers due to competition between Au–I covalent bonding and Au–Au aurophilic interactions. The covalent bonding favors a bent IAuIAuI– structure with an obtuse Au–I–Au angle (100.7°), while aurophilic interactions pull the two Au atoms much closer, leading to an acutely bent structure (72.0°) with an Au–Au distance of 3.08 Å. The two isomers are separated by a small barrier and are nearly degenerate with the obtuse isomer being slightly more stable. At low temperature, only the obtuse isomer is observed; distinct experimental evidence is observed for the co-existence of a combination of isomers with both acute and obtuse bending angles at room temperature. The two bond-bending isomers of Au2I3– reveal a unique example of one molecule being able to oscillate between different structures as a result of two competing chemical forces.

High-resolution state-selective autodetachment photoelectron spectroscopy via dipole-bound states and photodetachment spectroscopy of cryogenically cooled deprotonated thymine anions are reported., Deprotonated thymine can exist in two different forms, depending on which of its two N sites is deprotonated: N1[T–H]– or N3[T–H]–. Here we report a photodetachment study of the N1[T–H]– isomer cooled in a cryogenic ion trap and the observation of an excited dipole-bound state. Eighteen vibrational levels of the dipole-bound state are observed, and its vibrational ground state is found to be 238 ± 5 cm–1 below the detachment threshold of N1[T–H]–. The electron affinity of the deprotonated thymine radical (N1[T–H]˙) is measured accurately to be 26 322 ± 5 cm–1 (3.2635 ± 0.0006 eV). By tuning the detachment laser to the sixteen vibrational levels of the dipole-bound state that are above the detachment threshold, highly non-Franck–Condon resonant-enhanced photoelectron spectra are obtained due to state- and mode-selective vibrational autodetachment. Much richer vibrational information is obtained for the deprotonated thymine radical from the photodetachment and resonant-enhanced photoelectron spectroscopy. Eleven fundamental vibrational frequencies in the low-frequency regime are obtained for the N1[T–H]˙ radical, including the two lowest-frequency internal rotational modes of the methyl group at 70 ± 8 cm–1 and 92 ± 5 cm–1.

Goethe’s theory of world literature has spurred Chinese literature’s desire to join the world in the last 100 years. From Zheng Zhenduo’s “unification of literature” in the early twentieth century to “stepping into world literature” in the 1980s, the “global elements of twentieth century Chinese literature” at the turn of the twenty-first century and finally the “communication of Chinese literature overseas” of recent years, it has been a constant feature of Chinese literature’s global trajectory. This desire implies a conception of the relationship between Chinese literature and world literature that has experienced a number of transitions, from idealism to realism, from cosmopolitanism to localism, from import to export, yet “becoming world literature” has remained a constant pursuit.

Thermal stratification can occur when hot and cold fluids mix inside the pipeline of nuclear power plant, which can lead to temperature fluctuations with large amplitude and high frequency with time-varying wall heat stress and even induce thermal fatigue phenomenon. Therefore, how to accurately get temperature fluctuations of the inner wall without damaging the whole structure of the pipe system becomes the prime problem to be solved in the study of thermal fatigue. Base on energy conservation law, the non-iterative mathematic model of inverse heat conduction using the volume-control method has been developed in this paper for pipe in nuclear power plant. Numerical and experiment results show that the volume-control method can accurately catch the temperature fluctuation of different positions on the inner wall.

We herein report a novel Pt-based electrocatalyst for direct methanol fuel cells (DMFCs) using multi-walled carbon nanotubes (MWCNTs) supported manganese oxide and poly(3,4-ethylenedioxythiophene) (PEDOT) nanocomposite (MnO x –PEDOT–MWCNTs) as catalyst support for Pt nanoparticles. The prepared nanocomposites are characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and electrochemical tests. The results demonstrate that Pt nanoparticles are uniformly deposited on the surface of MnO x –PEDOT–MWCNTs, and their dispersion and electrochemical active surface area (ECSA) are obviously improved. The methanol electrooxidation activity and stability of the Pt/MnO x –PEDOT–MWCNTs are significantly enhanced as compared with the Pt/PEDOT–MWCNTs and Pt/MWCNTs catalysts. This study implies that the as-prepared Pt/MnO x –PEDOT–MWCNTs will be a promising candidate as an anode electrocatalyst in DMFCs.

To improve bulking agent reusability and reduce bulking agent costs, a new bulking agent was developed using straw and methylene diphenyl diisocyanate(MDI). The objective of this study was to investigate the characteristics of the new bulking agent. The new bulking agent was systematically evaluated by testing its water absorption characteristics and compression strength. The results showed that the new bulking agent has high compression strength, and when the proportion of bulking agent was between 25 and 33%, its water absorption capacity was maximized, and the moisture content of the mixture could be adjusted to approximately 60% with 24 h equilibration time. This study indicates that this new bulking agent is suitable for improving substrate structure and regulating moisture content during composting of sewage sludge.

The Bianbianshan deposit, the unique gold-polymetal (Au-Ag-Cu-Pb-Zn) veined deposit of the polymetal metallogenic belt of the southern segment of Da Hinggan Mountains mineral province, is located at the southern part of the Hercynian fold belt of the south segment of Da Hinggan Mountains mineral province, NE China. Ores at the Bianbianshan deposit occur within Cretaceous andesite and rhyolite in the form of gold-bearing quartz veins and veinlet groups containing native gold, electrum, pyrite, chalcopyrite, galena and sphalerite. The deposit is hosted by structurally controlled faults associated with intense hydrothermal alteration. The typical alteration assemblage is sericite + chlorite + calcite + quartz, with an inner pyrite – sericite – quartz zone and an outer seicite – chlorite – calcite – epidote zone between orebodies and wall rocks. δ34 S values of 17 sulfides from ores changing from –1.67 to +0.49‰ with average of –0.49‰, are similar to δ34 S values of magmatic or igneous sulfide sulfur. 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb data of sulfide from ores range within 17.66–17.75, 15.50–15.60, and 37.64–38.00, respectively. These sulfur and lead isotope compositions imply that ore-forming materials might mainly originate from deep sources. H and O isotope study of quartz from ore-bearing veins indicate a mixed source of deep-seated magmatic water and shallower meteoric water. The ore formations resulted from a combination of hydrothermal fluid mixing and a structural setting favoring gold-polymetal deposition. Fluid mixing was possibly the key factor resulting in Au-Ag-Cu-Pb-Zn deposition in the deposit. The metallogenesis of the Bianbianshan deposit may have a relationship with the Cretaceous volcanic-subvolcanic magmatic activity, and formed during the late stage of the crust thinning of North China.