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131.
南水北调中线工程对汉江中下游工业发展的影响 总被引:14,自引:3,他引:11
南水北调中线工程计划从丹江口水库向我国北方每年调水145亿m^3,汉江丹江口以下地区的水资源量将随之相应减少。汉江中下游地区是湖北省盐化工、机械、石油、食品、化肥、电力的重要生产地区,是湖北省的汽车工业走廊,其经济在湖北省占有举足轻重的地位。由于经济的迅速发展,下世纪工农业生产和人民生活对水资源的需求将从现在的140亿m^3增加到250亿m^3以上,需水量将达到水资源量的58%,潜伏着严重的水资源 相似文献
132.
Boqiang Cui Yin Liu Jinwen Bai Xianjie Du Changxiang Wang 《International Journal of Green Energy》2020,17(12):730-741
ABSTRACT In order to study the effect of fly ash content in cemented paste backfill (CPB) on its anti-sulfate erosion, the apparent phenomenon, strength development, and hydration products change the law of CPB with different fly ash content under long-term soaking of 5% sodium sulfate solution were studied by the macrotest and microanalysis, in addition, the mechanism of CPB anti-sulfate attack was analyzed by combining with a scanning electron microscope (SEM). The results indicated that the effect of sulfate environment on the strength of fly ash cemented paste backfill (FCPB) was mainly determined by the hydration products in the FCPB at different soaking times. In the early soaking stage, the formation of ettringite (AFt) in FCPB could improve its compactness, which was conducive to improving the strength of FCPB. In the late soaking stage, there were ettringite-type erosion damage and gypsum erosion-type damage internal of the FCPB with low content fly ash, resulting in microfracture, cracking of the FCPB, and reducing the strength. CPB with an appropriate content of fly ash could improve the internal structure of the FCPB to achieve the purpose of anti-sulfate erosion. 相似文献
133.
浅谈我国逆反射材料现状及其发展趋势展望 总被引:3,自引:0,他引:3
随着逆反射材料的广泛应用 ,其带来的安全警示效果、产品质量、生产工艺、检测方法及规范管理等方面的问题被日趋重视 ,笔者通过对逆反射材料的基本构造及反光特性的分析 ,论述了其对人和物的安全防护作用 ,并对我国目前逆反射材料的应用领域、产品质量及检测设备、检测标准等方面的问题进行探讨和评述 ,根据国内外的发展趋势 ,对我国开发及发展逆反射材料产业提出了笔者观点 ,为政府决策提供科学依据 相似文献
134.
中海石油企业安全文化建设 总被引:2,自引:1,他引:1
企业安全文化建设既是中海石油自身持续、稳定发展的客观需要 ,也是新形势下企业内、外部环境变化的客观要求。通过不断完善企业安全文化系统工程及其管理体系 ,将安全生产工作提高到文化的高度去认识 ,依靠安全文化的潜移默化作用 ,提高全体员工的安全意识和整体安全文化素质 ,让“我要安全”、“我会安全”贯穿于生产经营活动的所有时空、每一个环节 ,树立“以人为本的绿色能源生产企业”的良好社会形象 ,大力推广“本质安全化”理念 ,增强企业的抗风险能力和竞争能力 相似文献
135.
煤矸石山自然发火数学模型在红阳三矿新矸石山自燃防治中的应用 总被引:2,自引:1,他引:1
煤矿矸石山自燃现象普遍存在 ,对环境污染及危害极大 ,防治矸石山自燃是矿区环境修复的重点研究内容。笔者利用宏观的连续介质研究方法 ,以多孔介质流体动力学理论为指导 ,建立了煤矿矸石山自然发火数学模型 ,从数学上揭示了矸石山自燃的动态演变过程。通过分析矸石山内的渗流场明确了自然发火的影响因素及内在联系 ,针对红阳三矿新矸石山的自燃预防问题 ,提出了碾压、覆盖和边界注浆相结合的综合防治施工方案。该技术在红阳三矿新矸石山的现场应用表明 ,治理方案科学、经济、合理 ,实施效果良好。研究结果对预防矸石山自燃具有理论指导意义与实际应用价值。 相似文献
136.
带防腐层在役压力容器表面磁粉探伤灵敏度的试验研究 总被引:2,自引:2,他引:0
采用人工裂纹试样的方法 ,模拟压力容器涂刷油漆防腐层的状况进行磁粉探伤 ,得出了油漆防腐层厚度与裂纹检出灵敏度的定量关系 ;结合CVDA《压力容器缺陷评定》规范 ,探讨了试验方法对一般在役压力容器带有油漆的情况下 ,进行磁粉探伤检验的可行性。研究表明 :采用交流磁化法进行探伤 ,当漆层厚度大约小于2 5 0 μm时 ,灵敏度影响较小 ,同时亦表明不宜使用直流磁化方法。该结论对承受低应力工况条件下的压力容器安全质量检验和评估 ,具有重要参考价值 相似文献
137.
Ecological footprint (EF) has received considerable attention as a useful indicator in the context of sustainable development. So far, EF has been used in numerous studies by academies, organizations and government authorities. However, the results of these studies failed to be comparable directly with each other due to imprecise data sets, unmodified accounting methods of pasture and fossil energy, ignored secondary products, undefined process Of calculating yield factors and improper biocapacity for biodiversity. In this paper, we elaborated on EF estimating methods from six categories of consumption in order to overcome the limitations above. We adopted precise data and revised methods, calculated EF of some secondary products, introduced weighted factor to calculate yield factors and adjusted biocapacity by an appropriate amount. Meanwhile, we investigated the resource consumption of Liaoning Province in 2006 to assess EF. Its results showed that Liaoning Province overused its natural capital and was in an unsustainable state. We concluded that two specific problems that had arisen in EF assessment and gave some suggestions for Liaoning Province to improve its unsustainable state. 相似文献
138.
139.
Xiaoshuai Hang Huoyan Wang Jianmin Zhou Chengling Ma Changwen Du Xiaoqin Chen 《Environmental pollution (Barking, Essex : 1987)》2009,157(8-9):2542-2549
Soil pollution with potentially toxic elements (PTEs) resulting from rapid industrial development has caused major concerns. Selected PTEs and their accumulation and distribution in soils and rice (Oryza sativa) collected from Changshu, east China, were analyzed to evaluate the potential health risk to the local population. The soils were primarily contaminated with Hg, followed by Cu, Cd, Pb, and Zn. The concentrations of Pb, Hg, and Cd of 46, 32, and 1 rice samples exceeded their national maximum allowable levels in foods, respectively. Spatial distributions of total Cr, Cu, Pb, Zn, and Cd in soils shared similar geographical trends. The risk assessment of PTEs through rice consumption suggests that the concentrations of Cu, Pb, and Cd in some rice samples exceed their reference oral dose for adults and children. In general, there was no target hazard quotient value of any individual element that was greater than 1, but hazard index values for adults and children were 1.726 and 1.523, respectively. 相似文献
140.