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21.
张绍和 《探矿工程》1995,(4):25-25,29
研究了脉冲电镀法的优越性,合理选用了电镀复合片的镀层成分,室内试验表明:利用脉冲电镀法制造复合片及其钻头是可行的,使用结果比较理想。  相似文献   
22.
Solid phases, such as surface coatings (SC), suspended particulate matter (SPM) and deposited sediments (DS), contribute to the pool of heavy metals in natural waters. Their existing and forming conditions lead to potential differences in enrichment capacity of pollutants, chemical compositions and crystals. In this study, the contents of heavy metals in SC, SPM and DS were determined by GF-AAS after digestion with a mixture of concentrated HNO3 and HClO4. The selective extraction method was employed to remove Fe, Mn oxides and organic matters and associated heavy metals (Cu, Pb, Zn). X-ray diffraction analyses were performed to characterize the crystals in the samples. The results showed that no significant difference in the contents of Fe-oxides in DS, SPM and SC was found, but the contents of Mn-oxides and organic matter follow the order of SC〉SPM〉DS. The significant crystal characters were observed in DS, SPM and SC, and the kinds of minerals and crystallization degree follow the order of DS〉SC〉SPM. In addition, quartz was the most important matter of crystals in the solid phases. Enrichment capacity follows the order of SPM〉SC〉DS for Pb, Cu and Zn. Organic matter was the major sorbent for Cu, and Mn oxides and organic matter played an important role in the enrichment of Zn. However, Pb was absorbed mainly by Fe oxides. Moreover, compared with Fe oxides and organic matter, Mn oxides had a great enrichment capacity for these metals. Although DS, SPM and SC were formed in the same water system, contents of chemical components, crystals and enrichment capacities to heavy metals were obviously different.  相似文献   
23.
邢成起 《内陆地震》1998,12(2):119-125
干旱-半干旱地区冲洪积物顶面土壤中发育的砾石钙膜含有明显的年龄信息,其工及由统计计算得到的累积速率可用来估算所在冲洪积物或土壤的形成年代。  相似文献   
24.
孙书堂  严倩  黎宁  黄理金  帅琴 《岩矿测试》2020,39(3):408-416
多环芳烃(PAHs)是一类具有致癌作用且难以降解的持久性有机污染物,广泛存在于环境中。环境中痕量PAHs的直接分析往往因检测手段的检出限达不到要求而存在困难,需要结合分离富集手段。常规的样品前处理技术如索氏提取、液液萃取等存在耗时长、使用大量有机溶剂等问题。因此为了提高效率、避免对自然环境的二次污染,有必要开发一种简便、环境友好的新型样品前处理技术。固相微萃取(SPME)是一种集采样、富集、进样于一体的无溶剂前处理技术,与气相色谱-质谱(GC-MS)等技术联用可实现复杂基质中痕量有机物的快速富集和检测。目前SPME技术的研究热点主要集中在改善涂层的萃取性能以及提高其机械强度方面。本文采用铁丝(IW)作为载体,同时又提供了铁离子来源,以原位自转化的方式在具有良好机械稳定性的铁丝上生长出一层多孔结构的金属有机骨架化合物多孔膜[MIL-53(Fe)];将其作为固相微萃取涂层[IW@MIL-53(Fe)],以7种难挥发的稠环PAHs作为目标分析物,以浸入式模式进行萃取,并结合GC-MS作为检测手段验证其萃取性能。结果表明:新涂层的萃取性能是商用100μm PDMS涂层的1~2倍,且涂层可稳定使用120次以上。该方法的检出限为0.03~2.25ng/L,线性范围为250~10000ng/L,相关系数为0.9903~0.9991。将建立的方法应用于自然水体中PAHs的检测,加标回收率为80.1%~108.5%。本研究不仅为高性能SPME涂层简单、快速制备提供了新思路,而且所建立的方法有望应用于水体中痕量有机污染物的准确和高灵敏检测。  相似文献   
25.
以热浸镀Zn、0.2%Al-Zn-RE、5%Al-Zn-RE和55%Al-Zn-Si合金镀层钢丝为研究对象,进行了为期6个月的室内海水浸泡试验。结果表明,热浸镀Zn钢丝和0.2%Al-Zn-RE合金镀层钢丝的腐蚀速度是5%Al-Zn-RE和55%Al-Zn-Si合金镀层钢丝样品的2~3倍:同时建立了一种“极化-弛豫-电化学阻抗测量”的循环测试方法,对这几种热浸镀层在青岛海域海水中的腐蚀行为进行了初步探讨。  相似文献   
26.
为探究"矿物膜"中半导体矿物与光合色素间的日光响应协同作用,对采自安徽潜山市郊的"矿物膜"样品进行了矿物组成和色素组成分析。同步辐射X射线粉末衍射测定表明,样品富含锐钛矿、赤铁矿等半导体矿物;拉曼光谱证实其中存在地表广泛分布的光合色素:β-胡萝卜素。在此基础上开展锐钛矿-β-胡萝卜素协同增强日光响应模拟实验。合成锐钛矿电极并对其进行系统的矿物学表征,紫外-可见漫反射吸收谱计算其禁带宽度约为3.07 eV;莫特-肖特基计算得到的平带电位约为-0.16 V,载流子浓度约为3.25×1026 cm-3;光电化学测试结果显示其具有一定可见光光电转化能力。经β-胡萝卜素敏化处理后,锐钛矿电极平均光电流密度提升了400%,在425~550 nm间光吸收值提高,该波段位于日光辐射能量集中的波长范围内,且与β-胡萝卜素吸收范围吻合,表明二者间存在日光吸收及光电响应协同增强作用。  相似文献   
27.
The Buchan Formation sandstone reservoirs from the Ardmore Field in the UK Central North Sea are fluvial-aeolian deposits and provide examples of porosity preservation in deeply-buried reservoirs (2.7–3.2?km) caused by grain-coating illite/smectite (I/S). Here, high reservoir quality commonly correlates with the occurrence of grain-coating I/S and consequent inhibition of quartz cementation in the aeolian dune and interdune sandstones. Porosity is lower in fluvial sandstones lacking grain coating I/S but with intense quartz overgrowths. We propose that the presence of I/S reflects concentration of the smectitic-rich clay bearing water which would have been the deposits of the interdune and/or distal sector of fluvial distributary system, and were introduced into aeolian deposits by mechanical infiltration. Petrographic relationships indicate that these coatings grew mainly before the mechanical compaction as the clays occur at grain contacts. The use of empirical model suggested that about 6–7% porosity have been preserved. The burial-thermal history of the Ardmore area contributed to the high quality reservoir because throughout much of the time since deposition, the Devonian sandstones have been little buried. Only from the Palaeogene the reservoir temperatures exceeded about 70?°C and rapidly buried to today’s maximum depth, which have minimized the negative effect generally ascribed to smectitic clays on reservoir quality. The circumstances of porosity preservation shown in this study may be unusual, but nonetheless have profound consequences for exploration. It is possible to identify new Buchan Formation prospects in areas hitherto dismissed because they were generally assumed to be poor reservoir.  相似文献   
28.
The cross-sectional texture of rock varnish varies considerably with the scale of analysis and technique used to image a sample. Each jump in resolution results in new insight, with the current state-of-the-art resting at the nanoscale. One key to nanoscale analysis involves focused ion beam (FIB) techniques used most frequently in material science and semiconductor failure analysis. FIB preparation remains challenging, however, for samples like rock coatings with heterogeneous density and abundant porosity. A new technique involving multiangle ion thinning and in situ plan-view lift-out facilitated a scanning transmission electron microscopy study of rock varnish from Death Valley. The results reveal variability in lateral continuity of nanometer microlaminae that can be interrupted by post-depositional diagenesis involving leaching of Mn and Fe, and this variability could explain why some of the visual varnish microlaminations (VML) used in paleoclimatic research can sometimes appear discontinuous. Because these breaks result from post-depositional processes, they do not undermine the paleoclimatic interpretations of VML.  相似文献   
29.
邓海冬  帅琴  丁晓晓  顾涛  朱丹 《岩矿测试》2012,31(6):1015-1020
水体中正构烷烃的含量反映了研究区域有机物污染水平.痕量正构烷烃的测定常常需要结合分离富集方法才能保证灵敏度和选择性,液液萃取等常规分离富集方法存在耗时长、有机溶剂使用量大等缺点,而新型固相微萃取(SPME)分离富集技术相比而言具有高效简便、富集效率高的特点.本文采用溶胶-凝胶法自制稳定性和耐基质性能更优的有机-无机杂化SPME涂层,结合气相色谱-质谱(GC - MS)检测技术,对水样中26种正构烷烃进行同时测定.在优化的SPME - GC/MS条件下,采用浸入式萃取方式,萃取温度为25℃,萃取时间为30 min,26种正构烷烃的分析信号与浓度之间有良好的线性关系(线性相关系数为0.9935 ~0.9999),方法检出限为0.011 ~0.085μg/L(k=3),相对标准偏差(RSD,n=5)为3.9% ~10.0%.新型有机-无机杂化涂层与传统的分离富集技术相比,减少了有机溶剂的使用,提高了工作效率;与商用PDMS涂层相比,增加了正构烷烃同时检测的种类,提高了灵敏度,检出限低2~10倍.自制的有机-无机杂化SPME涂层体现出优异的分析性能和应用潜力.  相似文献   
30.
海拉尔盆地贝尔凹陷储层物性特征及控制因素   总被引:8,自引:2,他引:6  
贝尔凹陷铜钵庙组-南屯组的储层类型为中-低孔低渗型,存在两个异常高孔隙发育带:第一异常高孔隙带为1 300~1 800 m,第二异常高孔隙带为2 400~2 700 m。异常高孔隙发育带的控制因素为:①火山碎屑物质对孔隙的保存及其溶解形成的次生孔隙;②碎屑颗粒包壳对原生孔隙的保存;③大气水淋滤形成的次生孔隙;④有机酸溶蚀形成的次生孔隙。其中大气水淋滤形成的次生孔隙对异常高孔隙的贡献较小。由于贝尔凹陷内有机质热解产生的有机酸主要溶蚀对象是火山碎屑岩,且火山碎屑岩溶蚀产生的各种阳离子是绿泥石和伊利石的主要组成元素,所以贝尔凹陷异常高孔隙发育的根本控制因素是储层岩石类型的特殊性。  相似文献   
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