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著者人数: 19名, 形態: カラー図版あり, Number of authors: 19, Physical characteristics: Original contains color illustrations, Accepted: 2021-01-14, 資料番号: PA2110015000

As financial derivative products and systemic risk management tools, stock index futures and options have been greatly developed and widely issued in many countries. Taking the Shanghai Stock Exchange 50 (SSE 50) Index and its derivatives as the research objects, we first analyze the lead–lag relationship between stock index, index futures and index options in the Chinese mainland stock market based on a thermal optimal path (TOP) method whose essence is a non-parametric methodology, and compare the results with two mature markets, namely the Hong Kong and US stock markets. We find: (I) In US and Hong Kong stock markets, the index future leads the index. The index option leads the index future when the index remains stable or in an up-trend, but their lead–lag relation reverses when the index collapses; (II) In the Chinese mainland stock market, the index leads the index future, and the index option leads the index future in the whole period of our investigation; (III) In all three markets, the index option leads the index when the index remains stable or in an up-trend, but their lead–lag relation reverses when the index collapses. Our work gives new and strong evidence that the lead–lag relationship varies in different markets and with different market conditions, which has an important contribution to the reveal of the price discovery function of derivative products.

A melamine-organophosphinic acid salt (MDOP) was synthesized via neutralization of dibenzo[c,e][1,2]oxaphosphinic acid (DOPA) with melamine, and used as an additive-type flame retardant for epoxy resin (EP). Thermal stability and flame retardance was comprehensively evaluated via thermogravimetric analysis (TGA), UL-94 vertical burning test, limiting oxygen index (LOI) and cone calorimetry. The cured epoxy easily passed UL-94 V-0 rating with 0.33% content of P (5 phr MDOP); and LOI value of 38.0% was further achieved with 10 phr MDOP. The peak heat release (PHRR), total heat release (THR), total smoke production (TSP) and fire growth rate (FIGRA) were all reduced with the incorporation of MDOP. The pyrolysis behavior of the flame-retardant EP systems from Py-GC/MS and TG-FTIR suggested that MDOP played the role of flame retardance in both condensed and gaseous phases. Interestingly, the incorporation of MDOP did not deteriorate the mechanical properties of epoxy resin.

Electron-accepting molecules play an important role in developing organic solar cells. A new type of A-D-A molecule, 3,6-di([7-(5-bromothiophen-2-yl)-1,5,2,4,6,8-dithiotetrazocin-3-yl]thiophen-2-yl)-9-(2-ethylhexyl)carbazole, was synthesized. The lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) energy levels are −3.55 and −5.85 eV, respectively. Therefore, the A-D-A type of compound could be used as electron acceptor for fabricating organic solar cell with a high open circuit voltage. Gibbs free energy (−49.2 kJ/mol) reveals that the process of A-D-A acceptor accepting an electron from poly(3-hexylthiophene) at excited state is spontaneous. The value of entropy (118 J/mol) in the process of an electron transferring from P3HT to the A-D-A acceptor at organic interface suggests that electrons generated from separation of electron-hole pairs at donor/acceptor interface would be delocalized efficiently. Therefore, the A-D-A molecule would be a potential acceptor for efficient organic BHJ solar cells.

A series of planar 1,5,2,4,6,8-dithiotetrazocine derivatives were synthesized for study on charge transfer at donor/acceptor interface. The fluorescence quenching spectra, and the highest occupied molecular orbital (−6.10 ∼ −6.25 eV) and the lowest unoccupied molecular orbital (−3.45 ∼ −3.58 eV) energy levels of these 1,5,2,4,6,8-dithiotetrazocine derivatives show that they would be potential acceptor materials. Based on theoretical calculations, thermodynamic study on charge transfer at donor/acceptor interface was carried out. The results of experiments and theoretical calculations show that the electrons could transfer spontaneously from poly(3-hexylthiophene) to these acceptors. The percentages of fluorescence quenching increase with negative Gibbs free energy values increasing in the charge transfer procedures. Therefore, short circuit current values of organic solar cells would increase with the Gibbs free energy values increasing. This paper suggests a useful way for developing efficient organic solar cells.

The study of lead–lag relationship between stock index and stock index futures is of great importance for its wide application in hedging and portfolio investments. Previous works mainly use conventional methods like Granger causality test, GARCH model and error correction model, and focus on the causality relation between the index and futures in a certain period. By using a non-parametric approach—thermal optimal path (TOP) method, we study the lead–lag relationship between China Securities Index 300 (CSI 300), Hang Seng Index (HSI), Standard and Poor 500 (S&P 500) Index and their associated futures to reveal the variance of their relationship over time. Our finding shows evidence of pronounced futures leadership for well established index futures, namely HSI and S&P 500 index futures, while index of developing market like CSI 300 has pronounced leadership. We offer an explanation based on the measure of an indicator which quantifies the differences between spot and futures prices for the surge of lead–lag function. Our results provide new perspectives for the understanding of the dynamical evolution of lead–lag relationship between stock index and stock index futures, which is valuable for the study of market efficiency and its applications.

In this work, manganese porphyrins were immobilized on hybrid nanocomposite microspheres through amide bond using Fe 3 O 4 as hard templates. The catalyst was characterized by N 2 adsorption–desorption isotherm (BET specific surface area), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and ultraviolet and visible spectroscopy (UV–vis) analysis. The results showed the average size of the hybrid nanocomposite microspheres is 450 nm in diameter and the supported metalloporphyrin catalysts remained reactive after removing Fe 3 O 4 leaving the silica support with micropores. The catalytic performance of the as-prepared catalysts without Fe 3 O 4 core instead of with the core was significantly enhanced as a result of the homogeneous catalysis in a heterogeneous catalyst, and the conversion of ethylbenzene was up to 22.9%. The catalyst also possessed high stability, and could be reused 6 times without remarkable loss of the catalytic activity, compared to the unsupported counterpart.

In order to explore the safety performance of continuous structure bridge near fault zone, a typical three spans continuous girder bridge of highway was selected to study the structural seismic response. The finite element model of whole bridge considered the force characteristics of bearing and pile-soil interaction was constructed. Typical near-fault records were selected from the important earthquake events. Several artificial waves characterized with the soil type in bridge site were simulated and used for dynamic analysis. Comparing with the seismic response of bridge under three given acceleration design spectrum, the seismic performance of continuous bridge was studied by nonlinear dynamic time-history method. Research results indicates that, the seismic design spectrum considering near-fault effect, especially large amplitude pulse effect of near-fault records, will significantly enhance the seismic response of continuous girder bridge. The fact that the near-fault effect is not considered in China existing highway bridge seismic design code will increase the destructive risk of structure.

As the main body of the natural productivity, the urban greenbelt, an irreplaceable comprehensive ecological service system, plays a leading role in beautifying the urban appearance, improving the quality of the urban ecological environment, adjusting the urban ecological balance. The research of ecological service function assessment is a hot research of many domains in recent times, such as ecology, environmental science, sociology, science of culture, economics, etc. Technological innovation is not only the urgent need and significant support system of technological development, but also the urgent need of solving the existing problems of the ecological service function assessment of urban greenbelt. This paper analyzes the main barriers and corresponding countermeasures of the technological innovation, such as unsound innovation mechanism, dated technological means, fault information transform, unsound assessment system, etc., which provides enlightenment and reference for the assessment, planning, construction, management and sustainable development of the ecological service function of urban greenbelt.