石灰-粉煤灰改良高含水率疏浚淤泥的试验

针对我国大量发生的疏浚淤泥难以处理和污染环境的问题,采用生石灰和废弃粉煤灰为改良材料,通过置换试验和增加试验,研究石灰-粉煤灰改良淤泥的含水率、液塑限和无侧限抗压强度的变化规律.结果表明:改良土的含水率都会随着养护龄期的延长和材料添加量的增加而有效地降低;龄期和粉煤灰添加量对改良土的液塑限和塑性指数的影响较大;在石灰中添加粉煤灰作为辅助材料时,可以显著提高强度,在粉煤灰添加量为4倍的石灰添加量时比单独添加粉煤灰强度增长达10倍.     

石灰改良膨胀土膨胀性和水稳定性室内试验研究

针对安徽张庄矿尾矿坝填料膨胀土进行含水率、自由膨胀率δe f、膨胀力Pe和50 kPa压力下的有荷膨胀率δeP50试验,确定膨胀土的膨胀潜势及分布范围,采用掺石灰的方法对土体进行改良并进行击实试验,根据最大干密度和压实度96%制样,研究不同石灰掺量改良土自由膨胀率随养护时间的关系,进行干湿循环试验研究改良土的胀缩变形规律、渗透特性及抗剪强度特性.试验研究结果表明:随着石灰掺量的增加,膨胀土击实后最优含水率逐渐升高、最大干密度逐渐减小;改良土自由膨胀率随着养护时间的增加逐渐减小并于30 d之后趋于稳定;经历6次干湿循环后试样的胀缩变形存在着不可逆性,但掺灰量大于2%的改良土绝对膨胀率小于4%,试样表面无明显裂隙,抗剪强度提高明显,可认为试样膨胀性得到了良好的控制;对于相同石灰掺量的改良土,二次掺灰的改良效果要优于一次掺灰.     

流化床燃煤固硫灰固化淤泥质土路用性能研究

淤泥质软土通常难以满足路基工程填料要求.为利用淤泥质土和工业固体废弃物,采用流化床燃煤固硫灰固化淤泥质软土,通过标准击实试验、强度试验、水稳性试验,结果表明:掺加固硫灰使击实淤泥质土最佳含水量提高,最大干密度降低;固硫灰固化淤泥质土能提高淤泥质土的强度,符合路基填土要求;固硫灰最佳掺量为20%较合适,继续增大固硫灰掺量,所产生的强度增加幅度不明显,同时,在固硫灰中掺加适量石灰,强度可大幅提高;固硫灰能显著改善淤泥质土的水稳定性,这与固硫灰形成水硬性胶凝材料有关;固硫灰固化淤泥质土的微观形貌表明存在明显的火山灰反应.     

不同改良剂改良粉土的试验研究

结合泰州市东风路南段快速路改造工程,对泰州地区粉土进行室内改良试验,研究石灰-水泥和石灰-水玻璃作为改良剂对该地区粉土的改良效果。研究发现:石灰-水泥改良土最大干密度略高于素土的最大干密度,最优含水率与素土基本相同,改良土的无侧限抗压强度随着压实度增大而增加,随着龄期的增长改良土的强度明显提高;石灰-水玻璃改良土的最大干密度和最优含水率随着改良剂掺量的变化基本不变,最大干密度小于素土的最大干密度,改良土的强度随着压实度的提高而增大,但增加幅度不明显,石灰-水玻璃改良土中石灰、水玻璃组分掺量对改良土强度影响很大。     

花岗岩残积土路用性能石灰改良试验研究

为了改善云母含量较高、含水率较大的粗细粒含量近似等分花岗岩残积土路用性能,进行石灰改良处置,通过室内试验和现场检测,研究该石灰改良土路用性能变化规律和应用效果.试验结果表明:随着掺灰量增加,塑限上升、液限下降,但塑限变化大于液限;掺灰量与击实指标关系曲线存在平缓段,此时掺灰量适中(3%-5%);CBR(全称California bearing ratio,是美国加利福尼亚州提出的一种评定基层材料承载能力的试验方法)与掺灰量之间存在三次多项式关系,拟合方程参数受含水率控制,为石灰稳定土CBR强度值预估提供参考.同时探究泡水前后石灰改良土CBR强度值变化情况.对比现场试验段检测结果表明粗粒含量相近花岗岩残积土改良掺灰量为5%-6%为宜.     

水泥与粗颗粒工程弃土复合固化改良淤泥土试验研究

为实现工程弃土的资源化利用和降低工程投资,以苍南县安澜工程(南片海塘)护塘河开挖产生的淤泥质土为研究对象,将附近绿能小镇三澳核电站工程弃土作为粒径改良用土,并采用水泥作为固化剂,通过不固结不排水(UU)三轴剪切试验研究水泥与粗颗粒工程弃土复合改良淤泥土的物理力学性能,并得到即符合工程设计要求又具较好经济性的改良土配合比。试验结果表明,影响改良土物理力学性能因素主要为粗颗粒弃土占比、水泥掺量、养护龄期,其中水泥掺量与养护龄期影响最为显著;单掺改良时,粗颗粒掺量对改良土的力学影响较小,改良效果不佳。淤泥土、粗颗粒土、水泥掺量分别为40%、60%、15%,养护龄期为56 d时淤泥质土的改良效果最佳,最大偏应力和粘聚力分别为2897.87 kPa、567.63 kPa。改良后的土作为海塘闭气土方用土能够满足工程设计要求。该研究能够为海塘工程设计和施工提供理论依据和指导。     

工业废料改良膨胀土基本物理性质试验研究

研究利用工业废料铁尾矿砂和电石渣作为添加剂改良膨胀土的可行性与改良效果。通过室内试验,对铁尾矿砂改良土及铁尾矿砂-电石渣复合改良土的基本物理性质指标进行了研究。试验研究结果表明,单掺铁尾矿砂改良膨胀土,随着掺砂率的增加,改良土的自由膨胀率显著降低,界限含水率和塑性指数均降低。同时掺入铁尾矿砂和电石渣复合改良膨胀土的改良效果要优于单掺铁尾矿砂的改良效果。当铁尾矿砂掺量一定时,随着掺渣率的增加,改良土的自由膨胀率基本上是呈线性递减;改良土的液限降低,塑限先增大后减小,在掺渣率为10%时达到最大,从而改良土的塑性指数先减小后增大;在掺渣率为10%时达到最小。当两种材料掺量一定时,随着养护龄期的增大改良效果更为显著。当掺渣率一定时,随着铁尾矿砂掺量的增加,改良土的自由膨胀率、界限含水率和塑性指数仍均是降低的,与之前单掺铁尾矿砂改良膨胀土得出的结果相一致。说明掺铁尾矿砂和电石渣均对膨胀土的物理性质有显著影响,因此为膨胀土改良提供了一种新方法。     

滞洪区路堤改良路基填土CBR试验研究

滞洪区亚粘土作路基基层、底基层填料土必须进行固化改良,本文采用石灰—粉煤灰、水泥—粉煤灰组合和水泥—石灰组合对其进行改良研究,以承载比CBR值作为指标,针对不同的压实度、固化剂不同配合比掺量开展了系列试验,并进行了分析和讨论.试验结果表明,三种改良填料土的抗压强度,随着压实度增加,分别先呈现不同比例的增长,但增加到一定值后,开始趋于平稳或弱有减少,可控制压实度在93%～96%之间,能兼顾施工质量与经济.水泥—粉煤灰组合改良土和石灰—粉煤灰土在水泥或石灰掺量一定时,其承载比随着粉煤灰掺量的增大呈先增大后减少;水泥—石灰组合和石灰—粉煤灰组合改良土在水泥或粉煤灰掺量一定时,其承载比也随石灰掺量的增大呈先增大后减少.三种改良土粉煤灰、石灰掺量都存在最佳配合掺量,基于试验结果,笔者就三种改良路基土给出了建议的配比.     

石灰改良不同含砂率粉土室内试验研究

通过人工配制不同含砂率(10%、30%、50%)粉土,对其采用熟石灰进行室内改良试验,探究不同配比(3%、5%、7%)石灰改良剂对含不同砂率粉土的改良效果,结果表明:在本试验确定含砂率范围内,随着含砂率的增大,素土最大干密度先增大后减小,最优含水率保持在15%左右;对同一含砂率粉土而言,石灰改良土的最大干密度明显低于素土,加大石灰掺量时,这种趋势愈发显著;适当增大含砂率使得土颗粒中粗粒增多、级配更加合理,粉土的强度有着增大趋势;对于不同配比的石灰改良土,随着石灰掺量的增加,改良土的强度明显提高;在恒定压实度(96%)下,改良土的加州承载比(California bearing ratio,CBR,下同)要明显高于素土,改良剂对粉土起到很好的稳定作用.对比含砂率与改良剂掺量对粉土强度的影响,可以看出改良剂掺量对粉土强度起到决定性作用.该研究可为石灰改良粉土路基提供工程实用参考.     

南水北调东线工程高含水量疏浚淤泥材料化处理方法

针对南水北调东线工程中产生的大量高含水量疏浚淤泥处理难的实际工程问题,通过外加生石灰的方法对高含水量疏浚淤泥进行了改性处理,将高含水量疏浚淤泥处理成了一种可以作为淤泥堆场围堰、河堤培土加固等实际工程填土材料的松散良质土.室内试验结果表明:添加生石灰处理高含水量疏浚淤泥时,改良土塑性指数随着掺灰比的增加而降低;在同一掺灰比下,原泥初始含水量低的生石灰处理土的塑性指数比原泥初始含水量高的生石灰处理土低;处理土塑性指数的改变主要发生在龄期的前3 d.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the