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《Energy Policy》2014
AimThis study examines risk perceptions toward nuclear power before and after the Fukushima Daiichi disaster using nationally representative survey samples of American adults.ScopeOn March 11, 2011, a magnitude 8.4 earthquake, the largest in the nation's history, occurred off the coast of Japan. The earthquake produced a devastating tsunami that flooded areas of the Fukushima Daiichi nuclear plant and resulted in a loss of power to the plant's cooling system. In the weeks that followed, the world watched as Japanese and international nuclear power safety experts scrambled to contain the damage and prevent a full meltdown. Although the Fukushima Daiichi disaster was heavily covered in media, there is little empirical research on how this coverage impacted audience risk perceptions. Our analysis goes beyond examining aggregate risk perceptions, instead focusing on how specific sub-populations responded to the disaster.ConclusionWe found that ideological groups responded differently to the events in Japan. In particular, risk perceptions among conservatives decreased following the incident. Moreover, we found that media use exacerbated these effects. We discuss possible explanations for these findings. 相似文献
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在航天测控系统中,校相是日常设备维护必不可少的手段之一.通常情况下,校相的相位修正值是运用软件无线电的方法计算而得.矢量电压表是一种能同时测量信号幅度和相位的仪器,具有精度高、频带宽、灵敏度高的特点.利用矢量电压表测量和差通道相位差,计算出相位修正值,在硬件设备上实现了相位快速校准.该技术已在工程中成功实现. 相似文献
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动态信息网络是当前复杂网络领域一个极具挑战的新问题,其动态的演化过程具有时序、复杂、多变的特点.结构是网络最基本的特征,也是进行网络建模和分析的基础,研究网络结构的演化过程对全面认识复杂系统的行为倾向具有重要意义.使用“角色”来量化动态网络的结构,得到动态网络的角色模型,应用并改进多类标分类问题的“问题转换”思想,将动态网络的角色预测问题视为多目标回归问题,以历史网络数据作为训练数据构建模型,预测未来时刻网络可能的角色分布情况,提出基于多目标回归思想的动态网络角色预测方法MTR-RP.该方法不仅克服了基于转移矩阵方法忽略时间因素的不足,并且考虑了多个预测目标之间可能存在的依赖关系,实验结果表明,本文提出的MTR-RP方法具有更准确且更稳定的预测效果. 相似文献
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《Petroleum Chemistry U.S.S.R.》1988,28(4):253-261
- 1.1. Metal-containing (Me, Ni, Fe, Mo) boro- and ferrosilicate zeolites without a binder have high initial activities in hydrodesulphurization, similar to the activity of an industrial AlCoMo contact, but lower activities (by a factor of 2–3) in the stable process.
- 2.2. In catalysts consisting of γ-Al2O3 and group VI and VIII metal oxides, with low contents of active metals (Ni/Mo = 0·4−0·8) the addition of Ni and Na forms of boro- and ferrosilicates has a promoting effect, increasing stable values of activity by a factor of 2–3 and the apparent effective rate constant byb a factor of 4–7.
- 3.3. Introduction of sodium forms of boro- and ferrosilicates into an alumina matrix with a high content of active metals (Ni/Mo = 1·4−1·5) leads to inhibition hydrodesulphurization, reducing significantly (by a factor of 2·5−3) the stable values of activity and the apparent effective rate constant by comparison with the initial composition Al2O3 + NiO + MoO3.
- 4.4. The addition of 5–10% promoter (high-silica borosilicate zeolite) is optimum for modyfying the catalytic composition Al2O3 + NiO + MoO3.
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《Ceramics International》2020,46(13):21292-21303
Nanosized M-HNTs-MnO2 (Magnetic halloysite nanotubes-manganese dioxide) nanocomposite was synthesized by the reduction-precipitation method followed by the hydrothermal process. The existence of MnO2 nanoflakes on M-HNTs represents 3-D nanostructures without stacking of nanotubes and agglomeration. The sensor-based on M-HNTs-MnO2 nanocomposites exhibits higher sensor response (Rair/Rgas = 35.6) to 100 ppm of acetone gas at operating temperature (150 °C), with a short response-recovery time (3 s/7 s). The M-HNTs-MnO2 nanocomposite sensor shows excellent potential to act as a low cost, low-temperature sensor for acetone gas, with high acetone selectivity under high humidity conditions and with the interference of other gases. The high surface to volume ratio, three-dimensional nanostructure, and strong interactions between M-HNTs and MnO2 nanoflakes are accountable for the improvement of acetone sensing performance. Based on the high acetone selectivity, high stability and fast dynamic response, the M-HNTs and MnO2 sensor is an extremely appropriate candidate for a low-cost acetone sensor, and the projected approach offers a way to develop gas sensors that can be function at low temperatures for a wide variety of applications. 相似文献
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Environmental contamination such as soot particles and NOx has aroused extensive attraction recently.However,the main challenge lies in the oxidation of soot at mild temperature with the assistance of NOx.Here,a series of core-shell MnCeOx catalysts were successfully synthesized by hydrothermal method and employed for low-temperature catalytic oxidation of soot in the presence of NOx.X-ray diffraction(XRD),inductively coupled plasma-optical emission sp... 相似文献
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Topics in Catalysis - High reduction temperature generally induces the agglomeration of supported noble metals. Howerve, we found that high temperature reduction did not induce Pd particles... 相似文献
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Topics in Catalysis - In this study, we developed a novel combination model for different types of catalysts, which could generate synergistic effects for the catalysts with different functions. A... 相似文献