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Serious earthquake disasters not only cause power outages in distribution network, but also destroy transportation networks, which hinders the transportation of resources for restoration of distribution network and slows down the restoration. This paper proposes an improved resilience evaluation method and a resilience enhancement strategy of distribution network considering the effects of seismic attack on transportation networks. First, a seismic attack model is established to describe the relation between earthquake disasters and failure probability of transportation-distribution networks based on peak ground acceleration. The impact of earthquake disasters on transportation-distribution networks is quantified, and the failure scenarios are generated. Then, a resilience evaluation index is proposed by introducing the waiting time for road repair of emergency repair teams. Afterwards, a bi-level optimization model for distribution network restoration considering the fault line repair, the road repair, and the emergency resource scheduling is established and solved. The upper layer aims at the minimum power loss load, while the lower layer takes the minimum waiting time of the repair team as the goal. Finally, case studies on a coupling example of a 12-node transportation network and an IEEE 33-node distribution network verify the feasibility of the improved resilience index and the effectiveness of the proposed method. The results show that the resilience index considering seismic attack on transportation networks is accurate, and the restoration strategy can effectively enhance the resilience of distribution network in earthquake disasters.

The dominant bacteria isolated from grape surface (Vitis vinifera cv. Kyoho) were identified as Escherichia coli and Kocuria and inactivated by treatment with gaseous chlorine dioxide (ClO2) prepared by the indirect reaction between NaClO2 and dry ice, and the effects of ClO2 gas on bacterial inactivation were evaluated by measuring the logarithmic reduction of total bacterial counts. Meanwhile, during storage at 4 ℃ for 30 days, the color parameters, fruit hardness, percentage mass loss and total soluble solid (TSS) content of artificially inoculated grapes were measured to evaluate the effect of ClO2 gas on the quality of grapes. The results showed that ClO2 gas had a good inactivating effect on Escherichia coli and Kocuria inoculated on surface of grapes. When the cumulative concentration of ClO2 was increased from 131 to 599 μL/(L·h), the logarithmic reduction of Escherichia coli increased from 1.6 (lg(CFU/g)) to 3.5 (lg(CFU/g)), and the logarithmic reduction of Kocuria increased from 1.0 (lg(CFU/g)) to 4.5 (lg(CFU/g)). During 30 days of storage, the color of grapes treated with ClO2 gas did not obviously change compared with that of the untreated control group. The softening and mas loss were obviously inhibited and the consumption of soluble solids in grapes treated with the high cumulative concentration of ClO2 was obviously reduced after storage at 4 ℃ for 30 days compared with that in the control and low cumulative ClO2 concentration groups. Additionally, the residual ClO2 on grapes treated by ClO2 gas was less than 0.4 mg/kg during storage at 4 ℃ for 30 days. The ClO2 gas treatment method is convenient, efficient, and low cost, which can effectively kill bacteria and improve the quality of grapes. This study provides a technical basis for the application of ClO2 gas to fruits and vegetables.

High temperature melting vitrification is the safest and harmless disposal technology for fly ash from hazardous waste incineration. Fly ash with high calcium content was used as the research object to melt fly ash with low temperature by introducing SiO2, H3BO3 and CaF2 fluxing agents. The melting temperature, phase change and heavy metal leaching of fly ash were characterized by X-ray diffractometer, ash melting point analyzer and inductively coupled plasma atomic emission spectrometer. The results show that when the alkalinity of fly ash is adjusted to 1.10 by SiO2 (27.9%, mass fraction), CaSiO3 minerals with low melting point are formed, and the melting point of fly ash decreases from above 1 400 °C to 1 300 °C. H3BO3 (4.5%, mass fraction) and CaF2 (7.0%, mass fraction) are introduced as fluxing agents, and the melting temperature is further reduced to 1 200 °C, but SiO2 is overdoped. After optimization, the composite fluxing agent formula is SiO2 (20.0%, mass fraction), H3BO3 (4.5%, mass fraction) and CaF2 (7.0%, mass fraction), and the minimum melting temperature of fly ash is 1 124 °C, the vitreous content of the melt product reaches 87% (mass fraction), and the harmful substances of acid leaching are lower than the limit value, meeting the technical requirements of GB/T 41015-2021 standard for vitrification products. [ABSTRACT FROM AUTHOR]

Nano-silica has great potential in cement-based composites, but the agglomeration of nano particles in cement-based materials limits its development. A series of modified nano-silica were synthesized by grafting isobutylene alcohol poly-oxyethylene ether (TPEG) on to the surface of nano silica modified by silane coupling agent. The results show that the nano-silica modified by TPEG has better dispersibility and stability in an alkaline environment. In addition, compared with nano-silica, modified silica can make the cement hydration process controllable and improve the physical and mechanical properties of the mortar. [ABSTRACT FROM AUTHOR]

Based on the inheriting modern humanistic tradition of philosophy, Herder founds systematic culture philosophy by comparison, which consists of the principle of humanity, historicity and sympathy. It not only establishes thinking basis for spirit science, but aslo provives one of the most important thinking resources for the reviviscence of contemporary praxis philosophy. [ABSTRACT FROM AUTHOR]