Prediction method of sand-movement direction in rivers by geochemical elements

 The analysis of sand samples by X-ray fluorescent spectroscopy (XRF) gives the ratio of the geochemical elements to construct the sand samples. The application of the ratio matching to sand samples represents the correlation number between two sand samples with respect to geochemical elements. When the correlation number between two sand samples is low, the two samples are not geochemically similar each other. This denotes that the exchange of sand between two sampling points is scarce or the two samples are independent. When the correlation number between two sand samples is high, the two samples are geochemically similar, signifying that the exchange of sand between two sampling points is frequent or there is sand movement between two sampling points. If there exists prominent sand movement in the study area, the correlation number is almost 1 and kilo count number per second of each geochemical element per weight decreases along the flow direction. The decrease is caused by the reduction of sizes and the adherence of dirt on the surface of sand particles. Since the flow direction in rivers is usually the same as the direction of sand movement, it can be verified. This study obtains satisfactory results applying the method of prediction in sand movement to sediments in rivers. Received: 17 May 1995 · Accepted: 14 August 1995     

X射线荧光光谱测定荧光粉中硅铁锌钴

采用溶液法配制标准,粉末直接制备样饼,用SRS300型X射线荧光光谱仪测定彩色荧光粉中的SiO2、Fe2O3、Co、Zn组分含量,取得较满意的结果,与已知含量样品比较,所测组分的结果基本相符。精密度检验SiO2、Fe2O3、Co、Zn的RSD均<3%(n=10)。     

平直斜坡上破波带内质量输移流对污染物输移影响的数值研究

破波带内外都有质量输移流存在,其对破波带内污染物输移有怎样的影响,需要进一步深入研究。本文基于实验以及考虑质量输移流的对流扩散数学模型研究了平直斜坡上破波带内质量输移流对污染物输移影响。数学模型包括波浪模型、近岸流模型以及对流扩散模型。首先建立了破波带内污染物输移数学模型,其中波浪场基于波能守恒方程来计算,波导流场基于Longuet-Higgins提出的辐射应力模拟,污染物对流扩散方程中考虑了质量输移流的影响,并利用算例验证该数学模型。其次简要介绍了平直斜坡上破波带内污染物输移实验,并分析了污染物输移特性。连续投放污染物会形成污染带,本文分析了两种波况下不同时刻污染带与岸线夹角的变化,以及污染物在垂直岸线和沿岸线方向的输移速度,结果表明对两种波况来说在初始10-40s污染团向岸线方向输移速度分别约为0.05m/s、0.017m/s,之后速度分别减小为0.001m/s、0.011m/s。数值模拟结果与实验结果比较表明：考虑质量输移流的模拟结果与实验更为吻合。因而,通过实验以及数模研究表明破波带内质量输移流对破波带内污染物在垂直岸线方向的输移有重要影响,而对沿岸方向的输移则影响较小。     

高温高压密闭溶样-电感耦合等离子体质谱法测定荧光粉中的杂质元素

提出了一种采用高温高压密闭溶样快速消解荧光粉晶体的前处理新方法。针对目前常用的稀土氧化物和稀土磷酸盐类、碱土金属铝酸盐类、碱土金属硅酸盐类四大类荧光粉,研究了消解时间、温度、消解溶剂种类和用量4个条件对样品消解程度的影响。采用电感耦合等离子体质谱法(ICP-MS)测定了最佳消解条件下消解的荧光粉中杂质元素Cu、Zn、Cd和Pb的含量。结果表明:稀土氧化物和稀土磷酸盐类荧光粉的最佳消解条件为 2 mL HCl溶剂中120℃下消解3 h;碱土金属铝酸盐类荧光粉的最佳消解条件为2 mL HCl溶剂中160℃下消解6 h;碱土金属硅酸盐类的最佳消解条件为2 mL HCl+0.5 mL HF溶剂中160℃下消解3 h。荧光粉中主要共存元素对所测杂质元素Cu、Zn、Cd和Pb的检测无干扰。该法线性范围宽、检出限低、灵敏度高,是荧光粉晶体中元素检测的较佳方法。     

Study on Decoloration of Acidic Scarlet GR by Pyrolusite Oxidation under an Acid Condition

Decoloration of acidic scarlet GR by pyrolusite is studied in this paper. The effects of pH in solution, dosage and granularity of pyrolusite, reaction temperature, and vibration speed on decoloration efficiency are discussed. According to experiment results, the decoloration efficiency may exceed 95% for 40 mg/L GR solution by pyrolusite. pH is most important among all factors which impact the decoloration of acidic scarlet GR. Dosage and granularity of pyrolusite, reaction temperature, and vibration speed have a little benitfit on decoloration. The high decoloration efficiency and low removal efficiency of COD as well as FT-IR spectra of products between pyrolusite and acidic scarlet GR indicate that acidic scarlet GR undergoes the redox reaction on the interface of mineral and its chromophore is oxidated and decolored, but it is not removed thoroughly by oxidation.     

东海原甲藻线粒体细胞色素b(Cytb)基因的定量检测

建立了检测东海原甲藻线粒体细胞色素b(Cytb)基因mRNA含量的实时荧光定量PCR方法.以甲藻Cytb基因的简并引物扩增得到984 bp长的东海原甲藻Cytb基因片段,经克隆、测序,制备并纯化质粒.以光度法测定质粒浓度并作为标准品.对上述基因片段,利用PRIMER EXPRESS 3.0 设计引物,以梯度稀释的质粒标准品进行定量PCR反应,以SYBR Green I为荧光染料,制作标准曲线,得到基因拷贝数X与Ct值的关系为:Ct=-3.50 lg X+39.35(相关系数r为0.999).通过对不同生长时期的东海原甲藻样品的Cytb基因mRNA含量检测,发现该基因的表达量较稳定,平均值为(45.4±4.7)拷贝/细胞,受生长状态影响不大,可作为实时荧光定量PCR的内参基因.     

西南岩溶石山地区岩溶地下水示踪试验与分析——以湖南湘西大龙洞为例

围绕大龙洞水库成库条件调查中存在的疑点问题开展示踪工作。根据示踪试验区的水文地质条件,选择降雨时地表水向地下集中渗漏排泄的狗肉寨极乐村洼地落水洞作为投放点,并在极乐村洼地落水洞的北东大龙洞地下河出口附近的鬼冲地下河、鬼冲泉和大龙洞地下河出口下方对岸100m处的Y034季节性水点(表层带岩溶泉点)及大龙洞地下河出口设置接收点,采用弱酸性红A荧光染料类试剂作示踪材料。示踪结果显示,鬼冲地下河、鬼冲泉和大龙洞地下河与投放点的连通性差;季节性水点Y034与投放点的连通性好;表明通过狗肉寨极乐村洼地落水洞汇集转化成的岩溶地下水与表层岩溶带季节性岩溶泉水水力联系密切,而与鬼冲地下河、大龙洞地下河之间则存在有地下分水岭。      

Double funnelling in a mature coastal British Columbia forest: spatial patterns of stemflow after infiltration

Many studies have focused on the amount of stemflow in different forests and for different rainfall events, but few studies have focused on how stemflow intensity varies during events or the infiltration of stemflow into the soil. Stemflow may lead to higher water delivery rates at the base of the tree compared with throughfall over the same area and fast and deeper infiltration of this water along roots and other preferential flow pathways. In this study, stemflow amounts and intensities were measured and blue dye experiments were conducted in a mature coniferous forest in coastal British Columbia to examine double funnelling of stemflow. Stemflow accounted for only 1% of precipitation and increased linearly with event total precipitation. Funnelling ratios ranged from less than 1 to almost 20; smaller trees had larger funnelling ratios. Stemflow intensity generally was highest for periods with high‐intensity rainfall later in the event. The maximum stemflow intensities were higher than the maximum precipitation intensities. Dye tracer experiments showed that stemflow infiltrated primarily along roots and was found more frequently at depth than near the soil surface. Lateral flow of stemflow was observed above a dense clay layer for both the throughfall and stemflow experiments. Stemflow appeared to infiltrate deeper (122 cm) than throughfall (85 cm), but this difference was in part a result of site‐specific differences in maximum soil depth. However, the observed high stemflow intensities combined with preferential flow of stemflow may lead to enhanced subsurface stormflow. This suggests that even though stemflow is only a very minor component of the water balance, it may still significantly affect soil moisture, recharge, and runoff generation. Copyright © 2016 John Wiley & Sons, Ltd.     

Will harmful dinoflagellate Karenia mikimotoi grow phagotrophically?

We studied the phagotrophic ability of dinoflagellate strain Karenia mikimotoi KM-Lü (isolated from the South China Sea), using fluorescent microspheres, bacteria isolated from the culture of K. mikimotoi and a marine microalgae Isochrysis galbana. We found that K. mikimotoi cultured under conditions of high light intensity could ingest fluorescent microspheres (diameters 0.5 and 2.0 μm) and fluorescence-labeled bacteria and microalgae. Under a low light intensity, however, only fluorescent microspheres (diameter 0.5 μm) and fluorescence-labeled microalgae were ingested. K. mikimotoi showed better growth by ingesting living marine bacteria or microalgae I. galbana than the controls, either in nutrient-depleted or nutrient-replete conditions. In nutrient-depleted conditions, the growth of K. mikimotoi was more significant with I. galbana as the prey item. In conclusion, the harmful dinoflagellate K. mikimotoi from the South China Sea has apparent phagotrophic ability, and some marine bacteria and microalgae may promote the growth of K. mikimotoi.     

应用荧光显微技术判别吐哈盆地储层含油水性

通过在荧光镜下的油水特征实验，分别得出油、油包水、水包油、含油水、水的荧光特征，然后对吐哈盆地单井储层的油层、水层荧光特征反复实验，并与试油结果对比，归纳总结出了油层、水层及油水界面的识别标志。油层特征主要为荧光发光较好且均匀、大面积油包水；水层特征主要为荧光发光不均匀，可动水普遍，并出现水包油现象；油水界面特征主要为荧光从均匀发光过渡到不均匀发光，孔隙由可动油充填过渡到由可动水充填。提出了吐哈盆地储层含油规律性，从而为探井试油、油层划分提供了准确可靠的依据。