PS加固对非饱和遗址土的渗透特性影响研究

高模数硅酸钾（简称PS）对西北干旱区的土遗址具有明显的加固效果,其加固后的土体也具有较好的渗透性。采用VJ-T非饱和土渗透仪和常规压力板仪测试了PS加固前后饱和样的渗透系数和非饱和土的土-水特征曲线(SWCC),并利用相关模型预测了非饱和土的渗透系数。结果显示,PS加固以后,在各个含水条件下的渗透性都有一定程度的提高,7%PS加固样表现非常明显。其原因是PS与土颗粒进行了非常复杂的物理化学变化,在反应中颗粒的几何形状发生变化,大量棱角弱化或消失,土颗粒磨圆度变好。同时,孔隙壁变得光滑、平直,孔隙弯曲因子减小,有效孔隙增大,这些因素导致了非饱和黏土的渗透性能有较大幅度提高。电镜测试分析了PS加固以后黏土颗粒及孔隙的变化,较好地验证了渗透性试验的结果     

原子荧光法测量痕量汞的预处理实验

用原子荧光法测量地质样品中痕量汞,对两种不同的预处理方案进行了试验。通过国家一级地球化学标准物质中汞的测定,试验证实预处理时加入高锰酸钾的样品测量值更接近于标准值。     

川东北地区三叠系聚盐成钾机制及富集模式

川东北地区三叠系发育巨厚的蒸发岩层,并赋存优质的深层富钾卤水.因构造沉积条件的整体差异,川东北富钾卤水的成因机制与富集规律未有详尽研究.以"气钾兼探"为指导思想,综合利用野外露头?岩心?测井等资料,对川东北地区三叠系蒸发岩分布规律以及岩相古地理演化进行分析,明确了膏盐盆在T1j4?5?T2l1期间规模逐渐缩小、向SW逐...     

电感耦合等离子体发射光谱法和火焰原子吸收光谱法连续测定化探样品中12个元素

建立了地质化探样品中不同含量和检出限要求的12个元素的连续测定方法。样品经一次取样,用盐酸-氢氟酸-硝酸-高氯酸溶样,电感耦合等离子体发射光谱法测定铜、铅、锌、钴、镍、镉、锶、钡、钒、锰后,加碘化钾-甲基异丁基甲酮萃取分离,火焰原子吸收光谱法测定银、镉。银、镉的相对标准偏差(RSD,n=12)分别为6.5%、4.7%。与现行分析方法相比,建立的方法灵敏度和精密度高、准确度好,降低了生产成本,缩短了检测时间,尤其适合大量化探样品的测定。     

西藏甲玛铜多金属矿区成矿斑岩的岩浆混合作用:石英及长石斑晶新证据

西藏甲玛矿区斑岩内石英和长石斑晶的阴极发光(CL)特征及元素含量变化有效记录了岩浆演化、混合及补给事件.石英斑晶的显微生长结构表明,原始岩浆经历过2次铁镁质岩浆混合作用.根据石英斑晶中Ti含量的变化可知,在2次溶蚀前后,石英结晶温度分别增高了约110℃和80℃.此外,斜长石斑晶的反环带及其Ba、Sr、Fe等元素的浓度梯...     

软阳离子钾改性蒙脱石矿物对硝基苯的强化吸附实验研究

考察软阳离子钾改性蒙脱石在K+存在的条件下对硝基苯的强化吸附行为,详细分析比较了Henry和Fre-undlich方程对硝基苯吸附等温线的拟合结果,同时还进行了吸附热力学研究。实验结果表明,软阳离子钾对蒙脱石吸附硝基苯具有强化作用;硝基苯在蒙脱石上的吸附符合Freundlich和Henry方程,两模型方程线性拟合结果的相关系数均在0.96以上。热力学分析结果表明,硝基苯在蒙脱石上的吸附过程是一个自发的放热过程,说明蒙脱石对硝基苯的吸附主要由分配与EDA作用机制所控制。钾离子存在可为硝基苯吸附营造有利场所,不仅改善准入条件,同时增加某些吸附点位,从而促进并强化蒙脱石对硝基苯的吸附。     

福建云霄晶洞花岗岩及含石榴子石伟晶岩的硅氧同位素研究

在运用常规方法和激光烧蚀同位素分析方法分别对云霄晶洞花岗岩和伟晶岩(长石、石英和石榴子石)的硅、氧同位素组成进行研究的基础上,探讨了晶涧花岗岩及其含石榴子石伟晶岩的物质来源及形成条件.伟晶岩中的石英和长石的氧、硅同位素组成分别较之花岗岩中的石英和长石的氧、硅同位素组成,均未发生明显变化,表明二者岩浆来源一致.云霄县的乌...     

Heating Stage Experimental Study of Melt Inclusions in Feldspars from Three Holocene Eruptions of Changbaishan Tianchi Volcano

There occurred several eruptions from Changbaishan Tianchi volcano in Holocene, and at least three of them were believed to be true according to the formal studies. The products of three eruptions were yellow comenditic pumice of - 5000a B.P. （Eruption Ⅰ ）, gray comenditic pumice and pyroclastic flow of - 1000a B.P. （ Eruption II, i.e. the millennium explosive eruption）, black trachy pumice and welded tuff of - 300a B.P. （ Eruption Ⅲ ） respectively. There were a large number of melt inclusions found in phenocrysts, which differ in size and color. The Leitz 1350 heating stage experiments for melt inclusions in host feldspars from three Holocene eruptions of Changbaishan Tianchi volcano imply that there were little differences between the homogenization temperatures of melt inclusions from Eruptions Ⅰ and Ⅲ, whereas it was rather complicated for Eruption H, i.e. there might be two kinds of melt with different homogenization temperature periods, which gave the evidence for the assumption that the explosive millennium eruption of Tianchi volcano was triggered by injection and mixing of two different magmas. The experimental results also indicate that （ 1 ） small melt inclusion is easy to be homogenized, while the large one, especially the one with lots of daughter crystals, is rather difficult to be homogenized; （2） homogenization temperature closely correlates with the size of melt inclusion within host crystal, with the temperature point switching from high heating rate to low heating rate, and correlates with whether it is the first time to obtain homogenization as well; and （3） a melt inclusion can get different homogenization temperatures when it is repeatedly heated. Even more, the next homogenization temperature is usually higher than the former one, which testifies the phenomenon that hydrogen migration occurs during repeated heating.     

Effect of water quality on the leaching of potassium from sandy soil

When potassium (K⁺) fertilizers are applied to soil, K⁺ is subject to displacement through the soil profile. More generally, the application of K⁺ fertilizers to sandy soils with low clay content and small buffer capacity, in which K⁺ does not interact strongly with the soil matrix, results in localized increases in K⁺ concentration in the soil solution. Losses of K⁺ depend on the concentration of calcium (Ca²⁺) as a competing ion in the leaching water and the amount of water that passes through the soil. In this study, we examined the adsorption and movement of applied K⁺ in columns of sandy soil. Glass tubes, 4.8 cm in diameter and 40 cm in length, were packed with either native soil or Ca²⁺-saturated soil. The resulting 10-cm-long column of soil had a bulk density of 1.65 g cm⁻³. Native soil was leached with distilled water and CaCl₂ solutions of various concentrations. In the Ca²⁺-saturated soil, a pulse of K⁺ was leached with CaCl₂ solutions of various concentrations or distilled water. Increasing the CaCl₂ concentration from 3 to 15 mm resulted in earlier breakthrough, a higher peak concentration of K⁺, and greater amounts of leached K⁺. The breakthrough curve for K⁺, when leached with distilled water, showed very low concentrations and was more delayed than the other treatments. In Ca²⁺-saturated soil, the amount of K⁺ leached increased as Ca²⁺ concentration increased, with up to 54% of the added pulse K⁺ being removed from 10 pore volumes (Pv) (387 mm) of 15 mm CaCl₂. The presence of Ca²⁺ in irrigation water and soil minerals able to release Ca²⁺ is important in determining the amount of K⁺ leached from soils. Large amounts of K⁺ are leached from soils in areas where crops are irrigated with water that contains significant concentrations of Ca²⁺ and other cations.     

4A沸石分子筛对KNO3和NH4NO3的吸持作用

实验研究了4A沸石分子筛经熔融盐处理后对KNO₃和NH₄NO₃的吸持作用。结果表明：在实验条件下,KNO₃处理后的4A沸石中含钾(以K₂O计)15.01%,含NO^-₃ 9.23%;NH₄NO₃处理后的4A沸石中含NO^-₃ 10.78%,含NH⁺₄ 0.94%。熔融盐处理后的样品X射线衍射峰相对强度发生了变化,红外光谱中1 640 cm^-1附近水的吸收带强度减弱,1 390 cm^-1附近出现的NO^-₃离子的强吸收带及825 cm^-1附近出现的NO^-₃离子的弱吸收带,以及热重-差热曲线中KNO₃和NH₄NO₃的热失重和分解热效应均证明沸石中吸持盐的存在。处理后4A沸石分子筛的基本骨架结构没有被破坏,吸持盐的4A沸石对营养盐的储备大大提高,是潜在的缓释肥料。