摘要:
It is the fact that there are lots of hazard incidents in underground uranium mines caused by radon but in-suit uranium samples were difficult to collect. Based on closed chamber method, three similar samples in different sealed ways were made in a laboratory with different material rations, namely uranium tailings, quartz sand, cement, iron powder and silicon powder to measure the radon concentrations with and without low-frequency vibrations, which was used by the experimental device for low-frequency vibration diffusion of radon. The results showed that the radon exhalation coming from the similar samples was influenced by the low frequency vibration; the results are presented as two-stage variations compared with the blank group. The radon exhalation increased with the rising vibration frequency when the frequency was 50 to 70 Hz, but fell slowly after reaching the peak radon exhalation rate. Analyses of the relations between the rock damage degree, changes in porosity and the occurrence of an inflection point in the radon exhalation rate in the samples found that they also increased when the frequency was between 0 to 80 in sample 3. The maximum porosity of the third samples was about 4.8% with a low-frequency vibration 60 Hz, while the maximum damage degree was about 0.07 at 50 Hz.
作者机构:
[Xu, Shoulong; Zou, Shuliang] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Xu, Shoulong] Tsinghua Univ, Dept Engn Phys, Beijing 100084, Peoples R China.;[Han, Yongchao; Qu, Yantao] China Inst Atom Energy, Beijing 102413, Peoples R China.
通讯机构:
[Zou, Shuliang] U;Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Peoples R China.
关键词:
active pixel sensor;video monitor;radiation detector;radiation damage;radiation response;nuclear accident
摘要:
In this paper, we present the availability of an active pixel sensor (APS) with four transistors (4T) as a video monitor and radiation detector. Analyzing radiation damage must be one of the first steps in recovering from nuclear accidents, and the radiation response characteristic is the basis for the use of 4T-APS to detect radiation. The goal of this work is to suggest the use of cameras with 4T-APS in widely distributed irradiation detectors. The total ionizing dose (TID) of radiation damage on 4T-APS provided a threshold. Radiation tolerance was improved with the help of a radiation shielding structure. The radiation response showed integration time dependence and pixel information dependence, and greater radiation response was observed from the pixels with lower grayscale values. Two methods are suggested based on different monitoring scenes. This study can help to greatly improve nuclear accident emergency response and the safety of nuclear facilities.
期刊:
Journal of Cleaner Production,2018年196:1365-1378 ISSN:0959-6526
通讯作者:
Zhao, Guo-yan
作者机构:
[Liang, Wei-zhang; Zhao, Guo-yan] Cent S Univ, Sch Resources & Safety Engn, Changsha 410083, Peoples R China.;[Hong, Chang-shou] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Peoples R China.
通讯机构:
[Zhao, Guo-yan] C;Cent S Univ, Sch Resources & Safety Engn, Changsha 410083, Peoples R China.
关键词:
Circular economy (CE);Phosphorus chemical firm (PCF);Performance evaluation;Vlsekriterijumska optimizacija I;kompromisno resenje (VIKOR) method;Qualitative flexible (QUALIFLEX) method;Linguistic neutrosophic number (LNN)
摘要:
Confronting the dilemma of resource shortage and environmental pollution, the idea of circular economy (CE) has attracted widespread attentions. To address these problems, several industrial companies have incorporated the CE in their operation or design. In this sense, the phosphorus chemical firms (PCFs) are promoting CE to achieve sustainable development goals since phosphorus is a non-renewable resource and one of the nutrient elements essential for crop growth. Thus, this paper aims to find a suitable way to assess the performance of CE for PCFs. Firstly, the evaluation index system of CE is designed according to the characteristics of CE for PCFs. Then, a new framework based on the qualitative flexible (QUALIFLEX) and Vlsekriterijumska Optimizacija I Kompromisno Resenje (VIKOR) methods is established to pick out the best enterprise. The linguistic neutrosophic number (LNN) is advised to describe decision making information with linguistic true, hesitant and false membership degree. Moreover, an entropy-based approach is used to determine the index weights, and the VIKOR method is presented to determine the concordance index. After that, all possible permutations are itemized, and the ranking result is obtained according to the general concordance index values of each permutation: Finally, an example of assessing the performance of CE for PCFs in China is given to illustrate the proposed method, and its feasibility is demonstrated. The robustness and advantage of this approach are also indicated with sensitivity and comparison analysis. The results show that the proposed VIKOR-QUALIFLEX method is reliable and stable for assessing the performance of CE for PCFs, and provides references for the construction and management of CE for PCFs. (C) 2018 Elsevier Ltd. All rights reserved.