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根据Biot理论,利用势函数方法建立了频域内孔隙介质的二维格林函数;利用格林函数和孔隙介质中的互易定理,建立了孔隙介质的边界积分方程.通过引入二维弹性静力学解和二维La-place方程的基本解,处理了边界积分方程中的柯西主值积分问题.笔者的研究为应用边界元方法求解孔隙介质中的二维动力问题提供了理论基础. 相似文献
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为了研究人工抽水对滨海潜水含水层的影响,采用二维渗流槽试验模拟非完整井抽水对咸淡水界面的影响。抽水导致咸水升锥的形成和海水入侵,结合图像处理技术,用海水楔长度和面积随时间的平均变化率定量表征海水入侵的速率。结果表明,在海水楔平衡后,咸水升锥位于抽水井靠近向海边界一侧。抽水量为34.8mL/min时,咸水楔的顶端与井底处在同一水平面上,最终抽水井出水中海水的含量基本恒定。在此基础上进行抽水恢复试验表明,停止抽水后海水楔可基本恢复至抽水前的状态。无论是在抽水还是停止抽水后,相对于总体变化趋势,海水楔长度的变化均滞后于海水楔面积的变化。 相似文献
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张国辉 《建设科技(建设部)》2015,(1)
文章主要通过对青岛市海水综合利用和海水淡化产业化发展现状研究,分析了青岛市在海水综合利用及海水淡化产业发展的布局和做法,通过剖析制约我国海水淡化产业发展的主要因素,提出了政府引导、政策鼓励、法规支持、示范带动等长效的管理机制,为进一步加快我国海水综合利用及淡化产业化发展提供帮助。 相似文献
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土-结构相互作用中侧向人工边界的影响 总被引:1,自引:0,他引:1
采用通用有限元程序ANSYS,针对某一桥墩与地基土层相互作用进行了二维有限元计算,并分析4种侧向人工边界时的影响。计算中均匀地基土体的本构模型采用ANSYS程序里的D rucker-Prager模型,通过地震波输入,对土体4种人工边界进行计算讨论,并确立粘-弹性人工边界作为土体的侧向边界。 相似文献
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采用通用有限元程序ANSYS,对某一桥墩与地基土层的相互作用进行了二维有限元分析,土体的本构模型采用ANSYS程序中的Drucker-Prager模型,土体边界采用粘—弹性边界人工边界,通过计算,得到了土结构相互作用对结构动力分析的影响以及土体性质、上部结构刚度不同时相互作用体系的动力特性。 相似文献
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An in situ time-integrating seawater sampler in which air escaping from the sample bottle through a capillary regulates flow of seawater into the sampler is described for determination of average plant nutrient concentration during a 10–50 h period. The sampler collected water at a constant rate which was approximately equal to that predicted from the Hagen-Poiseuille equation. The sampler has advantages over those described previously: it is less susceptible to blockage from suspended particulates in seawater, less expensive, and the seawater collection rate should be less temperature-dependent. 相似文献
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在分析海水入侵形成机理的基础上,从特殊地质环境及相关自然因素和人类工程经济活动两大方面分析了深圳市海水侵入的原因,启示我们在大力发展经济建设时,应统筹考虑对人类生存的自然环境的保护,不能以牺牲生态环境来换取经济效益。 相似文献
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Kuniaki Takagi Tatsumi Inamura Masahiro Kawajiri Kazuo Noya Yoshitugu Hagiwara Yasunobu Suketa 《Water research》2002,36(1):239-247
Deep seawater has recently been under trial as a fundamental material for mineral water, food, face lotion and an efficacious reagent for the cure of atopic dermatitis in Japan. However, little is known about the biologically effective substances, including toxic compounds in deep seawater. In this study, we investigated the effects of deep seawater on the function of murine macrophages in vitro, and examined the endotoxin-like substances in seawater. Mitochondrial activity and NO production in macrophage cells cultured with stimulants were enhanced in a depth dependent manner by pretreatment with deep seawater. In addition, fractions from deep seawater, enriched by hydrophobic column chromatography, activated the macrophage cells much more than the corresponding fractions from surface seawater. Furthermore, the effects of the fractions on macrophage cells remained significant, even with the addition of polymyxin B. which is a specific inhibitor of endotoxins. These results indicate that endotoxins and unknown substances, which affect macrophage functions, exist in a depth dependent manner in seawater. 相似文献
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镁基海水海砂混凝土以海砂为唯一骨料,以原状海水为拌合水,具有较高强度。硫氧镁水泥MOS含量为16%时,28d抗压强度达59MPa以上、抗折强度达10MPa以上;含量增至20%时,28d抗压强度达72MPa以上、抗折强度达16MPa以上。试验证明,使用较少的镁基胶凝材料即可使海水海砂混凝土达到较高强度,满足多种建材产品的强度要求。同样,氯氧镁水泥MOC含量为25%时,7d抗压强度达68MPa以上,28d抗压强度达94MPa以上。海水拌合海砂混凝土以镁基胶凝材料通过改性剂及掺合料控制海砂中游离氯离子的含量,克服硫酸盐硫酸根离子与混凝土孔隙中的钙离子发生反应,提高混凝土材料的强度和耐久性。以原状海水代替淡水直接拌合,就地取材,以盐治盐,施工成本低廉,经济优势明显。 相似文献
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The failure of a large percentage of previously monodispersed virus added to artificial seawater to pass through membrane filters which would exclude the passage of aggregates indicated that extensive aggregation was taking place in artificial seawater. The loss of viral titer in artificial seawater was found to be directly related to salinity as was the extent of aggregation. Aggregation also appeared to be taking place in natural seawater, but was not as extensive. Viral clumps formed in both natural and artificial seawater could be disaggregated by an increase in the amount of organic matter or a decrease in salinity. Aggregation may play a role in the initial decline of viral titer in seawater, as well as to reduce the number of “infectious foci” present in seawater. 相似文献