高岭土/肼插层材料的制备与表征

以高岭土为原料,选取50%水合肼作为插层剂,采用直接液相插层法,并辅以磁力搅拌,成功地将肼分子插入到高岭石结构层间,制得肼插层高岭土材料。利用红外光谱和粒度分析仪对产品进行了表征。IR谱表明, 插层中肼分子中的NH基与高岭石内表面羟基之间产生了N-H-OH作用,形成了新的氢键;插层反应后的样品,其粒径小于5 μm的颗粒占总颗粒数的比例降低了10.55%,平均粒径增大了46.84%。     

135~130 Ma: 大别山第二次“去根”时间？

大别杂岩主要由早白垩世侵入岩和三叠纪变质岩组成。它的四周是四条区域性韧性剪切带:郯城—庐江断裂,商城—麻城断裂,襄樊—广济断裂和晓天—磨子潭断裂。其中,晓天—磨子潭断裂和襄樊—广济断裂在早白垩世具有相反的走滑剪切方向:北侧的边界断裂(晓天—磨子潭断裂)是一个左行剪切断裂,而南侧的边界断裂(襄樊—广济断裂)是一个右行剪切断裂。在大别杂岩内部,早白垩世低角度剪切面理的倾伏向以SE向或NW向为主。这些晚期剪切面理上的拉伸线理的倾伏向同样为SE或NW向。大别杂岩总体具有朝SE向挤出和顶部相对朝NW向剪切的构造特征。这些表明晚中生代是该杂岩演化的重要阶段。该杂岩的边界断裂和内部构造特征指示其晚期抬升是沿造山带方向(SE—NW)以低角度方式进行的。这一过程直接导致高压-超高压变质岩和同构造岩浆岩被抬升至近地表。同时,年代学研究表明:大别杂岩(扬子板块东北缘地壳)在晚侏罗世—早白垩世经历大规模混合岩化的时间为145~135 Ma,同造山岩浆作用的时间为145~135 Ma,后造山火山-岩浆活动的时间为135~120 Ma。因此,该杂岩中三叠纪高压-超高压变质岩所记录的早白垩世抬升过程不是印支事件的后续,而是燕山期陆内造山及随后发生的伸展过程有关。尽管这一陆内造山事件的起始时间至今仍不确定,但大别山未变形岩体(130~120 Ma)的年代学研究结果和我们新测得的同构造伟晶岩脉的锆石U-Pb年龄(130 Ma)为早白垩地壳变形提供了良好的上限制约。这样,大别山经历了三叠纪碰撞造山和伸展,晚侏罗世—早白垩世陆内造山-伸展二次过程。     

粉煤灰污染影响萼花臂尾轮虫(Brachionus calyciflorus)种复合体空间分布的原因

为探讨粉煤灰污染影响萼花臂尾轮虫(Brachionus calyciflorus)种复合体在灰湖、汀棠湖和凤鸣湖分布的生态学机制,本文研究了曝气自来水(对照)、20％、40％、60％、80％和100％的澄清灰湖水对采自三湖泊中的轮虫姐妹种Ⅰ和汀棠湖中的轮虫姐妹种Ⅱ的种群增长率、混交雌体数/非混交雌体数、携卵雌体数/不携卵雌体数和休眠卵产量的影响.结果显示,无论实验用水中的澄清灰湖水含量如何,来自三湖泊的轮虫姐妹种Ⅰ均具有较高的种群增长率(0.52～0.85 d-1)和休眠卵产量(1.60～12.11ind./(4d·5ml)),这为轮虫的扩散、种群的建立和种群间的基因交流提供了可能.汀棠湖轮虫姐妹种Ⅱ种群中的混交雌体数/非混交雌体数和休眠卵产量均极低,对照组中的混交雌体数/非混交雌体数和休眠卵产量均为0,这是存在于汀棠湖和凤鸣湖中的轮虫姐妹种Ⅱ无法通过扩散而出现在灰湖中的主要原因.澄清灰湖水的含量仅对汀棠湖中两轮虫姐妹种的种群增长率具有显著的影响.各浓度的澄清灰湖水使轮虫姐妹种Ⅰ的种群增长率显著高于对照组,60％、80％和100％的澄清灰湖水使轮虫姐妹种Ⅱ的种群增长率显著高于对照组,这表明粉煤灰污染导致已报道的相关水体中轮虫种群密度的下降并非由于其中所含的污染物(较高浓度的碱性氧化物、硫化物和金属元素等)和水体pH值的改变等对轮虫的直接毒性作用.     

Sensitive Ion‐Flotation Separation of Ag(I) Traces Using 2‐(2‐Methoxyphenyl)benzimidazole before Flame Atomic Absorption Spectrometric Determination in Water

A sensitive, reliable, and environmentally friendly method for simple separation and preconcentration of Ag(I) traces in aqueous samples is presented prior to their flame atomic absorption spectrometric determinations. At pH 7.0, Ag(I) was separated with 2‐(2‐methoxyphenyl)benzimidazole (MPBI) as a new complexing agent and floated after adding sodium dodecyl sulfate (SDS) as a foaming reagent. The floated layer was then dissolved in proper amount of concentrated nitric acid in methanol and introduced to the flame atomic absorption spectrometer (FAAS). The effects of pH, concentration of MPBI, type and amount of surfactant as the floating agent, type and amount of eluting agent, and influence of foreign ions on the recovery of the analyte ion were investigated. Also, using a nonlinear curve fitting method, the formation constant of 1.62 × 10⁶ was obtained for Ag(I)–MPBI complex. The analytical curve was linear in the range of 1.8 × 10^?7–1.7 × 10^?6 mol/L for determination of Ag(I). The relative standard deviation (RSD; N = 10) corresponding to 0.7 × 10^?6 mol/L of Ag(I), the limit of detection (10 blanks), and the enrichment factor were obtained as 1.7%, 2.9 × 10^?8 mol/L, and 43.0, respectively. The proposed procedure was then applied successfully for determination of silver ions in different water samples.     

大水金矿床金的迁移形式和沉淀机制探讨

基于大水金矿床地质特征和矿物流体包裹体显微测温研究成果,对金在成矿过程中的迁移形式和沉淀机制进行了探讨。研究认为,金矿床在主成矿作用过程中金主要以AuC12-、Au(HS)2-、AuH3SiO40形式迁移,少量以硫络合物、硫氢络合物、胶体溶液、砷络合物(配合物)及地幔流体等形式迁移。推断水—岩反应(尤其是硅化和硫化作用)和以深部流体为主与古大气水的均一化流体的混合作用以及在此过程中的降温减压作用是金沉淀的重要机制。     

太行山东麓构造岩浆带在豫北安林地区的活动特点及控矿特征

安林地区的构造活动,对剖析太行山东麓构造岩浆带成生、演化具有一定的代表性。本区自燕山运动开始就受到了变质核杂岩和伸展拆离构造控制,区内主要构造有NNE向和NW向两组,其中NNE向构造在区内等间距形成了五条规模大的深断裂,均具高角度正断层性质。NW向构造形成了天喜镇-磊口北西向构造岩浆岩带,包括了塔山穹窿式背斜和白玉村-宝山墙状岩体,两组构造均对燕山晚期中-碱性岩浆上侵和安林式矽卡岩型铁矿的形成具重要控制作用。     

Torsional dynamic response of a large‐diameter pipe pile in viscoelastic saturated soil

An analytical solution is developed in this paper to investigate the dynamic response of a large‐diameter end‐bearing pipe pile subjected to torsional loading in viscoelastic saturated soil. The wave propagation in saturated soil and pile are simulated by Biot's two‐phased linear theory and one‐dimensional elastic theory, respectively. The dynamic equilibrium equations of the outer soil, inner soil, and pile are established. The solutions for the outer and inner soils in frequency domain are obtained by Laplace transform technique and the separation of variables method. Then, the dynamic response of the pile is obtained on the basis of the perfect contacts between the pile and the outer soil as well as the inner soil. The results in this paper are compared with that of a solid pile in elastic saturated soil to verify the validity of the solution. Furthermore, the solution in this paper is compared with the classic plane strain solution to verify the solution further and check the accuracy of the plane strain solution. Numerical results are presented to analyze the vibration characteristics and illustrate the effect of the soil parameters and the geometry size of the pile on the complex impedance and velocity admittance of the pile head. Finally, the displacement of the soil at different depth and frequency is analyzed. Copyright © 2014 John Wiley & Sons, Ltd.     

Contamination of a well in a uniform background flow

In this paper we describe the transport of pollution in groundwater in the neighbourhood of a well in a uniform background flow. We compute the rate at which contaminated particles reach the well as a function of the place of the source of pollution. The motion of a particle in a dispersive flow is seen as a random walk process. The Fokker-Planck equation for the random motion of a particle is transformed using the complex potential for the advective flow field. The resulting equation is solved asymptotically after a stretching transformation. Finally, the analytical solution is compared with results from Monte Carlo simulations with the random walk model. The method can be extended to arbitrary flow fields. Then by a numerical coordinate transformation the analytical results can still be employed.     

鲁西新泰孟家屯2.7Ga变质沉积岩与黑云斜长片麻岩锆石Hf同位素特征

对出露于山东新泰孟家屯2.7Ga的孟家屯岩组中石榴石石英岩(M08)、含十字石石榴石黑云母石英片岩(D242-Y2)和黑云斜长片麻岩(M03)(TTG质片麻岩)进行锆石Lu-Hf同位素分析。石榴石石英岩锆石核部176Lu/177Hf、176Hf/177Hf变化范围为0.001730～0.002546、0.281249～0.281360,锆石变质边部176Lu/177Hf、176Hf/177Hf变化范围为0.000123～0.002070、0.281241～0.281318;含十字石石榴石黑云母石英片岩锆石核部176Lu/177Hf、176Hf/177Hf变化范围为0.001334～0.002169、0.281226～0.281324,锆石变质边部176Lu/177Hf、176Hf/177Hf变化范围为0.000445～0.001375、0.281227～0.281309;黑云斜长片麻岩锆石176Lu/177Hf、176Hf/177Hf变化范围为0.000315～0.000847、0.281186～0.281265。孟家屯岩组石榴石英岩、含十字石石榴石黑去母石英片岩中碎屑(岩浆)锆石和黑云斜长片麻岩中岩浆锆石的εHf(t)分别为3.75～7.26、2.31～7.26和3.21～6.27,同时TDM1与其U-Pb年龄非常接近,表明它们起源于新生地壳的部分熔融。结合区域研究资料认为,2.7Ga是鲁西重要的一期构造岩浆热事件,也可能是华北克拉通重要的构造岩浆活动时期。变质沉积岩中许多变质增生锆石相对于核部岩浆锆石低176Lu/177Hf、高176Hf/177Hf,显示变质作用过程中石榴石的存在对锆石的Lu-Hf同位素体系有很大影响。     

甘肃北山勒巴泉变质核杂岩

在多期伸展体制下形成的勒巴泉变质核杂岩构造,具有3层结构的特征,即结晶基底、中间韧性盖层、上部脆性盖层,其间分别被基底剥离断层和盖层剥离断层分割。本文重点论述了变质核杂岩的组成、空间展布、结构构造和典型的构造样式,并分析了变质核杂岩构造的形成时代和大地构造背景。