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351.
首先对水面舰船风浪环境适应性的内涵进行了分析,重点研究了风浪环境对舰船综合航行性能及作战使用效能的影响.考虑到实际风浪环境中舰船各项总体性能指标是一个复杂的体系,各指标之间既具有矛盾性又具有一致性,是一个多目标、多变量的复杂系统.提取了跟风浪环境相关性较强的船体性能指标,建立了水面舰船风浪环境适应性多级综合评价指标体系.进而应用多级模糊综合评价模型,建立了舰船风浪环境适应性评估方法,对某深V船型和圆舭船型的风浪环境适应性进行评估,深V船型评估结果为66.95,圆舭船型为50.5,验证了评估模型的合理性.采用4种不同评判矩阵对两船风浪环境适应性进行了评估,结果表明,评判矩阵的选取对评估结果有较大影响.  相似文献   
352.
An innovative approach of using waste glass in cement production was proposed and tested in a laboratory and cement production plant. The laboratory characterization of 32 types of glass show that the chemical composition of glass does not vary significantly with its color or origin but depends on its application. The alkali content of glass, a major concern for cement production varies from 0 to 22%. For the glass bottles mainly found in Hong Kong waste glasses, the alkali content (Na2O) ranges from 10 to 19% with an average around 15%. There is no significant change of the SO2 content in the gas exhaust of the rotary kiln when about 1.8 t/h of glass bottles were loaded along with the 280-290 t/h raw materials. The content of NOx, mainly depends on the temperature of the kiln, does not show significant change either. The SO3 content of the clinker is comparable with that obtained without the loading of glass. The alkaline content shows a slight increase but still within three times the standard deviation obtained from the statistical data of the past year. The detailed analysis of the quality of the cement product shows that there is not any significant impact of glass for the feeding rate tested.  相似文献   
353.
以氧化石墨烯(GO)为原料制备MnO2@Fe3O4/石墨烯(RGO),考察吸附过程中MnO2@Fe3O4/RGO投加量、溶液pH值、初始浓度和吸附时间等因素对Pb(Ⅱ)的去除率和吸附量的影响,并运用BET比表面积测试法计算MnO2@Fe3O4/RGO的比表面积和平均孔径,采用扫描电子显微镜(SEM),振动样品磁强计(VSM),X射线衍射(XRD)和X射线光电子能谱(XPS)等对样品进行表征.结果表明:MnO2@Fe3O4/RGO的比表面积为89.164m2/g,孔容为0.284cm3/g;随着pH值在2~10范围内增加,复合材料对Pb(Ⅱ)的去除率先增大后减小,pH=6时达到最大值.通过4种等温吸附模型(Langmuir、Freundlich、Temkin、D-R模型)和4种吸附动力学模型(伪一级动力学、伪二级动力学、Elovich、颗粒内扩散模型)拟合发现,MnO2@Fe3O4/RGO对Pb(Ⅱ)吸附符合伪二级动力学模型.吸附等温线更符合Langmiur模型,属于典型的单分子层吸附,以化学吸附为主,最大吸附量为265.3mg/g.  相似文献   
354.
Journal of Material Cycles and Waste Management - The qualified green lightweight aggregate (LWA) was successfully prepared from steel mill sludge (SMS) and fly ash (FAS) in one step using the...  相似文献   
355.
Previous assessments of the effectiveness of protected areas (PAs) focused primarily on changes in human pressure over time and did not consider the different human-pressure baselines of PAs, thereby potentially over- or underestimating PA effectiveness. We developed a framework that considers both human-pressure baseline and change in human pressure over time and assessed the effectiveness of 338 PAs in China from 2010 to 2020. The initial state of human pressure on PAs was taken as the baseline, and changes in human pressure index (HPI) were further analyzed under different baselines. We used the random forest models to identify the management measures that most improved effectiveness in resisting human pressure for the PAs with different baselines. Finally, the relationships between the changes in the HPI and the changes in natural ecosystems in PAs were analyzed with different baselines. Of PAs with low HPI baselines, medium HPI baselines, and high HPI baselines, 76.92% (n=150), 11.11% (n=12), and 22.86% (n=8) , respectively, showed positive effects in resisting human pressure. Overall, ignoring human-pressure baselines somewhat underestimated the positive effects of PAs, especially for those with low initial human pressure. For PAs with different initial human pressures, different management measures should be taken to improve effectiveness and reduce threats to natural ecosystems. We believe our framework is useful for assessing the effectiveness of PAs globally, and we recommend it be included in the Convention on Biological Diversity Post-2020 Strategy.  相似文献   
356.
Chao  Ling  Sun  Yajun  An  Zhen  Li  Juan  Wu  Weidong  Liu  Yue  Song  Jie 《Environmental science and pollution research international》2022,29(11):15999-16005
Environmental Science and Pollution Research - Previous studies have reported regional variations in the relationship between ambient temperature and dermatitis, which therefore remain...  相似文献   
357.
Environmental Science and Pollution Research - Runoff forecasting is essential for the reasonable use of regional water resources, flood prevention, and mitigation, as well as the development of...  相似文献   
358.
Environmental Science and Pollution Research - With the increase in global population, industrialization, and urbanization, waste from construction, renovation, and demolition (CRD) activities has...  相似文献   
359.
Environmental Science and Pollution Research - The problems of data leakage and unreliable information transfer in the management process make sustainability management an inevitable need for...  相似文献   
360.
Li  Yongjun  Qiao  Jing  Xie  Lei  Huang  Lingyan  Su  Yue  Zhou  Mengmeng  Wang  Ke  Zhang  Jing  He  Shan  Huang  Lu 《Environmental science and pollution research international》2022,29(31):46751-46766

To achieve urban sustainability, it is critical to enhance the environment, economy, and society simultaneously. This study adopted the revised genuine progress indicator (GPI) and ecological footprint (EF) to evaluate the ecological efficiency and economic sustainability of the Yangtze River Delta from 2000 to 2018. Spatial analysis was utilized to identify spatial autocorrelation. A total of 27 cities were then partitioned through k-means cluster analysis. The results showed that GPI and ecological efficiency improved rapidly, but economic sustainability showed a downward trend. GPI and GDP had a high degree of spatial correlation, especially in Suzhou-Wuxi-Changzhou Metropolitan Area. However, no spatial correlation existed between GPI and EF. The city with high GEE can reach 3000 $/gha, indicating the city consumed 1 global hectare to create $3000 of genuine economic growth. Shanghai, Hangzhou, and Taizhou were cities with the highest level of economic sustainability and ecological efficiency. The spatiotemporal characteristics of economic sustainability and ecological efficiency revealed in this study will provide theoretical guidance for alleviating ecological pressure and promoting economic sustainable development.

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