[en] Fluorescent and colorimetric recognition properties of 2-(4-N-phenyl-3-thiosemicarbazone)-8-hydroxyquinoline (1) in buffered aqueous solution (1% DMSO, HEPES 20 mM, pH = 7.4) have been examined. Sensor 1 displays highly selective and sensitive recognition to Cu²⁺ with fluorescence 'ON-OFF' performance. The in situ formed 1-Cu²⁺ complex exhibits an excellent selectivity toward sulfide ions with fluorescence 'OFF-ON' behavior via Cu²⁺ displacement approach. Thus, relay recognition of Cu²⁺ and sulfide by a known molecule 1 has been achieved

[en] This paper restudies the method of direct chelatometric titration of V(IV) with N-benzoyl-N-phenylhydroxylamine (BPHA) as indicator. The indicator functions entirely differently from indicators hitherto used in chelatometry. The solution contains two independent systems - the indicator and the titrand-titrant system - without any color changing species. The BPHA-V(V) chelate once formed as the result of aerial oxidation constitutes the indicator system and does not react with EDTA. Its color therefore remains unchanged throughout titration. It is not a metallochromic indicator. Its function is that of color-screening. The color of the titrant system deepens during titration, but does not change. The end-point is indicated by one color completely covering up the other. Hence, this method is of purely empirical nature. Refs. 12 (author)

[en] We prove that in a two-dimensional homogeneous boson system with Rashba spin–orbit coupling, Bose–Einstein condensate with plane-wave order is unstable at finite temperature. The calculations are based on a nonlinear sigma model scheme. The density wave contributions to the thermal deletions are divergent in the infrared limit. The behavior of the divergence is different from that without spin–orbit coupling

[en] The electronic structures of amorphous Nb/sub 100-x/Ni/sub x/ (x=65, 59.8, 56.4) alloys are studied by means of UV-photoelectron spectroscopy (UPS). It is found that the Fermi level is located near the minimum of the density of states, which explains the double Curie-point phenomena in Nb-Ni alloys. Analyzing the electron structure of Nb-Ni alloys, it is pointed out that the hybridization of two d-bands with energies close to each other may form a new hybridized band near E/sub F/ and the hybridization is related to the valence difference. The charge transfer causes the peaks of the bands to shift. The density of states of T/sub E/-T/sub L/ alloys at E/sub F/ should include two contributions, i.e., that from 3d electron states, which is of advantage to magnetism, and that from 4d electron states, being of advantage to superconductivity. Different ratios of these contributions at E/sub F/ greatly influence the magnetism and superconductivity of the alloys. The coexistence of localized magnetic moments and superconductivity has also been discussed

[en] Chitosan-clinoptilolite composite was prepared and tested for removing radiocobalt from aqueous solution. The composite was characterized with Fourier transform infrared spectroscopy, X-ray diffraction analysis and scanning electron microscopy coupled with energy dispersive X-ray analysis. The sorption of Co(II) on chitosan-clinoptilolite composite was pH-dependent and ionic strength-independent. The kinetic sorption was fitted well by a pseudo-second-order rate equation. The thermodynamic parameters (ΔH0, ΔS0, ΔG0) revealed that the sorption of Co(II) on chitosan-clinoptilolite composite was spontaneous and endothermic. The study showed that chitosan-clinoptilolite composite had excellent potential for the treatment of wastewater containing radiocobalt. (author)

[en] A new phenylbenzimidazole derivatized fluorescent sensor (L) with 2-picolylamine as Zn²⁺ chaltor was designed and prepared. In buffered water solution (HEPES 10 mM, pH 7.4), sensor L displays highly selective, sensitive and ratiometric fluorescent recognition to Zn²⁺ based on inhibition of excited-state intramolecular proton transfer (ESIPT). In addition, the resultant L–Zn²⁺ complex exhibits ratiometric responses to S²⁻ with excellent selectivity via S²⁻ induced Zn²⁺ displacement approach. The results demonstrate that L can serve as a ratiometric fluorescent sensor for relay recognition of Zn²⁺ and S²⁻ in water at physiological pH. -- Highlights: • A new phenylbenzimidazole derivatized fluorescent sensor L was synthesized. • Sensor L displays high selectivity to Zn²⁺ ion in water solution with ratiometric fluorescence changes. • The in situ generated L–Zn²⁺ complex exhibits highly selective recognition to S²⁻via Zn²⁺ displacement approach. • Relay recognition of Zn²⁺ and S²⁻ was achieved through modulating ESIPT

[en] A new quinoline-based acylhydrazone (1) has been synthesized and applied as a fluorescent probe. Probe 1 exhibits high selectivity and sensitivity to Cu²⁺ with fluorescence 'ON-OFF' behavior in HEPES buffered (1% DMSO, HEPES 20 mM, pH = 7.4) solution. The on-site generated 1-Cu²⁺ complex displays excellent selectivity to sulfide ions with fluorescence 'OFF-ON' performance through copper displacement approach

[en] Scientifically evaluating the level of low-carbon development in terms of theoretical and practical significance is extremely important to coal enterprise groups for implementing national energy-related systems. This assessment can assist in building institutional mechanisms that are conducive for the economic development of coal business cycle and energy conservation as well as promoting the healthy development of coal enterprises to realize coal scientific development and resource utilization. First, by adopting systematic analysis method, this study builds low-carbon development evaluation index system for coal enterprise groups. Second, to determine the weight serving as guideline and criteria of the index, analytic hierarchy process (AHP) is applied using integrated linear weighted sum method to evaluate the level of low-carbon development of coal enterprise groups. Evaluation is also performed by coal enterprise groups, and the process comprises field analysis and evaluation. Finally, industrial policies are proposed regarding the development of low-carbon coal conglomerate strategies and measures. This study aims mainly to guide the low-carbon development of coal enterprise groups, solve the problem of coal mining and the destruction of ecological environment, support the conservation of raw materials and various resources, and achieve the sustainable development of the coal industry.

[en] Identifying influential nodes in complex networks is of both theoretical and practical importance. Existing methods identify influential nodes based on their positions in the network and assume that the nodes are homogeneous. However, node heterogeneity (i.e., different attributes such as interest, energy, age, and so on) ubiquitously exists and needs to be taken into consideration. In this paper, we conduct an investigation into node attributes and propose a graph signal processing based centrality (GSPC) method to identify influential nodes considering both the node attributes and the network topology. We first evaluate our GSPC method using two real-world datasets. The results show that our GSPC method effectively identifies influential nodes, which correspond well with the underlying ground truth. This is compatible to the previous eigenvector centrality and principal component centrality methods under circumstances where the nodes are homogeneous. In addition, spreading analysis shows that the GSPC method has a positive effect on the spreading dynamics. (paper)

[en] Further development of earthquake equipments is closely associated with that of computer technology. Because Embedded PC104 module has the equivalent functions of PC, it has been widely used in recent years, and can provide a new and flexible hardware design environment, but its applications in observation instruments of earthquake precursor are rare. The present paper introduces in detail the realization of a networked geo-electrical meter by applying the low price, high reliability embedded PC104 industrial computer.