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361.
<正>近年来,攀枝花市防震减灾宣传工作牢固树立以人为本的基本理念,坚持贴近实际、贴近生活、贴近群众的宣传方针,围绕服务大局、服务经济、服务群众,在宣传防震减灾方面的新思路、新举措、新成果、新经验等方面做了大量卓有成效的工作,搭建了一个有利于更好开展防震减灾工作的平台,取得了明显的实效,有力地推动了全市防震减灾 相似文献
362.
对目前我国房屋建筑中一种最为广泛应用的结构形式房屋——多层砌体房屋进行震害预测分析研究,简要介绍六种常用的多层砌体震害预测方法,易损性概率分析法或称为半经验半理论法、强度判别法、延性系数判别法、模糊类比法、人工神经网络法和结构理论计算法,在详细调查房屋基本情况的基础上,综合考虑以上几种方法,提出相应的震害预测的分析方法。对郑东新区砌体房屋进行震害预测,做出该地区的震害矩阵,并给出该地区砌体房屋在地震作用下的破坏程度及相应震害面积。 相似文献
363.
364.
Chao?Yan Heidi?M.?Nepf Wei-Xi?HuangEmail author Gui-Xiang?Cui 《Environmental Fluid Mechanics》2017,17(3):497-519
Predicting flow and mass transport in vegetated regions has a broad range of applications in ecology and engineering practice. This paper presents large eddy simulation (LES) of turbulent flow and scalar transport within a fully developed open-channel with submerged vegetation. To properly represent the scalar transport, an additional diffusivity was introduced within the canopy to account for the contribution of stem wakes, which were not resolved by the LES, to turbulent diffusion. The LES produced good agreement with the velocity and concentration fields measured in a flume experiment. The simulation revealed a secondary flow distributed symmetrically about the channel centerline, which differed significantly from the circulation in a bare channel. The secondary circulation accelerated the vertical spread of the plume both within and above the canopy layer. Quadrant analysis was used to identify the form and shape of canopy-scale turbulent structures within and above the vegetation canopy. Within the canopy, sweep events contributed more to momentum transfer than ejection events, whereas the opposite occurred above the canopy. The coherent structures were similar to those observed in terrestrial canopies, but smaller in scale due to the constraint of the water surface. 相似文献
365.
Junhong Yang Xuyang Cui Yuanzheng Feng Guangning Jing Ligai Kang Mengyuan Luo 《International Journal of Green Energy》2017,14(15):1269-1276
Microalgae have been identified as a superior feedstock for biodiesel production and varied tubular photobioreactors are developed for high efficient and scale-up microalgae cultivation. This article presented a novel concentric double tubes using aeration through radial pores along the length direction of inner tube. Experiments on microalgae cultivation were carried out in the novel photobioreactor, and two control groups including concentric double tubes with axial aeration at both ends and common tubular. The biomass productivity of novel photobioreactor increased by 43.6% and 107.4%, respectively, compared with concentric double tubes with axial aeration at both ends and common tubular without aeration. The values of pH shifted from 7.5 to 9.0 for novel photobioreactor, but 7.5 to 8.8 for common tubular, and 7.5 to 9.6 for concentric double tubes with axial aeration. The dissolved oxygen concentration fluctuated between 6.0 and 7.0 mg·L?1 for novel photobioreactor, but rose from 6.6 to 10.2 mg·L?1 for the common tubular, and 6.9 to 8.1 mg·L?1 for the concentric with axial aeration. Results show that the aeration style of novel photobioreactor can make efficient local mixing and maintain smaller range of pH and lower level of dissolved oxygen in case of higher biomass concentration. Moreover, compared with the two control groups, the novel concentric double tubes have advantages on the light/dark cycle frequency, which may be benefit for microalgae cultivation. The novel concentric double tubes presented in this work can give some inspiration for high efficiency microalgae cultivation. 相似文献
366.
You-Wei Cui Hong-Yu Zhang Si-Yuan Ji Zhi-Wu Wang 《Journal of Polymers and the Environment》2017,25(2):277-285
Haloferax mediterranei is an extremely halophilic archaeon that is able to synthesize polyhydroxyalkanoate (PHA) in high salt environment with low sterility demand. In this study, a mathematical model was validated and calibrated for describing the kinetic behavior of H. mediterranei at 15, 20, 25, and 35 °C in synthetic molasses wastewater. Results showed that the production of PHA by H. mediterranei, ranging from 390 to 620 mg h?1 L?1, was strongly dependent on the temperature. The specific growth rate (µ max), specific substrate utilization rate (q max), and specific decay rate (k d) of H. mediterranei increased with temperature following Arrhenius equation prediction. The estimated activation energy was 58.31, 25.59, and 22.38 kJ mol?1 for the process of cell growth, substrate utilization, and cell decay of H. mediterranei, respectively. The high temperature triggered the increased PHA storage even without nitrogen limitation. Thus, working at high temperatures seems a good strategy for improving the PHA productivity of H. mediterranei. 相似文献
367.
Zhang Cuixia Wang Cui Gao Mengdi Liu Conghu 《Environmental science and pollution research international》2023,30(9):22375-22387
Environmental Science and Pollution Research - The sustainability of industrial production systems is considered to be the key to promoting green transformation and upgrading of manufacturing... 相似文献
368.
Li Jing Sun Jingjing Wang Ruonan Cui Tiejun Tong Yindong 《Environmental science and pollution research international》2023,30(8):20121-20132
Environmental Science and Pollution Research - A variety of physical, chemical, and biological processes within the lakes relies on the surface water temperature while the spatial pattern of large... 相似文献
369.
Wu Jian Cui Chunying Mei Xiaolong Xu Qingsong Zhang Pu 《Environmental science and pollution research international》2023,30(10):25037-25049
Environmental Science and Pollution Research - At present, China’s carbon emissions rank first in the world, which not only brings huge challenges to the sustainable development of... 相似文献
370.
在我国黄土丘陵地区,每年因为高填方边坡失稳而造成的人员伤亡和财产损失数不胜数,有必要从高填方边坡的填料入手,开展高填方边坡失稳问题研究。以陕西某高填方边坡为例,将高填方边坡的碎石填料作为主要研究控制对象,取其边坡正在填筑的碎石填料,通过诸多室内试验测定物理力学参数、渗透性等,并借助FLAC 3D数值模拟计算其稳定性,先确定最优土石比,再确定在最优土石比下的优选级配。择优选择的级配相比之前的填料,力学性能更好,强度更高,隔水效果控制更明显,坡体的整体稳定性加强。从填方填料入手,能有效降低因回填材料不合理而引发的边坡失稳。 相似文献