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The distribution of radioactive pollutants, such as222Rn, U, Th and226Ra in the air, surface waters, soils and crops around the Lincang uranium mine, Yunnan Province, China, is studied. The mechanical, geochemical and biogeochemical processes responsible for the transport and fate of the radioactive elements are discussed based on the monitoring data. The pollutants concentrations of effluents from the mine tunnels were dependent on pH and which were controlled by biochemical oxidation of sulfide in the ore/host rocks. Radon anomalies in air reached 4 km from the tailings pile depending on radon release from the site, topography and climate.238U and226Ra abnormities in stream sediments and soil were 40—90 cm deep and 790—800 m away downstream. Anomalies of radioactive contaminants of surface watercourses extended 7.5—13 km from the discharge of effluents of the site mainly depending on mechanical and chemical processes. There were about 2.86 ha rice fields and 1.59 km stream sediments contaminated. Erosion of tailings and mining debris with little or no containment or control accelerated the contamination processes.

For emergent production interruptions in supply chain affected by disasters, an emergency decision model with multiobjective and multi-constraints for distribution plan is proposed. In this model, two objectives, profit level and shortage cost, are considered by characterizing the performance and demand of satisfaction of decision-makers. According to preferences of decision makers, three rules of constraints satisficing decision are proposed, and a corresponding algorithm with constraint satisficing optimization is presented. The satisficing solution of the model gives the planning of time and quantity for sale in distribution after production interruptions. Finally, a case study and comparative analysis are given. The work of this paper shows that the proposed emergency decision model can help to improve the profit level and reduce shortage cost in supply chain with production interruptions caused by disasters. And the model can be used as an effective decision tool for collaboration in coproduction enterprises facing production interruptions.

In this paper, related research works on catastrophe response methodology are reviewed from perspectives of catastrophe scenario analysis, response preparedness planning, response tasks planning and fault-tolerant design for critical infrastructure. For the need of catastrophe response tasks planning, a conteptual framework of response-preparedness methodology for system modeling and deployment is proposed, which is on the base of interrelated response and preparedness.

Aimed at no suitable online measuring instrument for circular pitch error of hob chip pocket, a new online measuring system using the half bridge inductive sensor DGC-6PG/A is put forwards into application in this paper. Measuring method and the structure of measuring system is introduced. Basing on making use of integrated signal conditioning circuit and Δ-Σ Analog-to-Digital converter, the system has combined high speed over sampling method and average filtering method to fulfill the high precision measurement of circular pitch sub-micron error. Experimental data according the adoption of inductive sensor and integrated signal conditioning circuit proves that stability performance better than ±0.01μm when sampling speed is limited under 100 Hz. So this online measuring system has high precision and lowers the surveyors’ complex work.

A Schottky type light-emitting diode of ZnO nanowire was fabricated based on the principle of luminescence of Schottky barrier heterojunction. Driven by a voltage of above 6 V, an EL spectrum was obtained. The spectrum consisted of two peaks: one is centered at a wavelength of the ultraviolet 392nm, and the other at the visible 525nm. The mechanism of electroluminescence of this device was analyzed according to the rectifying I-V curve and the energy band structure.