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1.
曾惠芳  周绍箕 《岩矿测试》1994,13(4):259-263
研究了三烷基氧膦纤维素色层分离富集痕量元素W、Mo和Sn的条件,根据吸附与洗脱实验中的现象初步探讨了TRPO与W、Mo,Sn的反应机理。以Rh为内标采用感耦等离子体质谱法进行测定,标准加入回收率为98%-101%;W、Mo,Sn的测定下限分别为0.02、0.01、0.1μg/g;重复取样测定的RSD均小于10%。经对地球化学标准物质分析,结果与推荐值相符。  相似文献   

2.
样品经HNO_3-HF-HClO_4分解,在5.4mol/L的HCl介质中,以抗坏血酸为还原剂用甲基异丁基甲酮同时萃取样品中的Se、Te。以Pd和Ni作混合基体改进剂,使用自制的涂锆石墨平台直接测定有机相中的Se、Te。方法的检出限分别为0.21×10 ̄(-9)gSe,0.13×10 ̄(-9)gTe;测定0.06gSe、0.03gTe的RSD(n=11)分别为7.0%和8.9%。  相似文献   

3.
设计的在线液液萃取分相器及相应流路系统与电感耦合等离子体原子发射光谱联用具有良好的分析性能。用于测定地质样品中的Mo和W,检出限(3σ)分别为36μg/L和28μg/L,两元素在0~2.0mg/L有良好的线性。对于1mg/L的Mo和W的测定,RSD(n=7)分别为40%和27%,测定速率为25~30/h。  相似文献   

4.
混合表面活性剂存在下锰的高灵敏显色反应研究   总被引:2,自引:0,他引:2  
尹家元  杨光宇 《岩矿测试》1998,17(4):282-284
研究了碱性介质中,Mn(Ⅱ)被空气氧化生成H2MnO3,然后在H3PO4介质中,Cu(Ⅱ)和阳离子型有机相/水相微乳液(CTMAB/戊醇/正庚烷/水)的存在下,Mn(Ⅳ)与二安替比林对乙氧基苯基甲烷(DApEM)生成橙色产物,λmax为450nm,ε=1.95×105L·mol-1·cm-1。Mn(Ⅱ)的质量浓度在0~320μg/L内符合比尔定律。方法用于合金中锰的测定,结果与标准值符合,5次测定结果的RSD<3%。  相似文献   

5.
在十二烷基硫酸钠存在下,于pH48~74的缓冲溶液中,2_〔2_(6_甲基苯并噻唑)偶氮〕_5_二乙氨基苯甲酸(6_Me_BTAEB)与Co(Ⅱ)发生显色反应,形成稳定的蓝紫色络合物,其组成为nCo(Ⅱ)∶n6_Me_BTAEB=1∶2,最大吸收波长为650nm,ε为138×105L·mol-1·cm-1,Co(Ⅱ)质量浓度在0~032mg/L时服从比尔定律。方法可直接用于维生素B12和含钴分子筛中微量Co(Ⅱ)的测定,结果与原子吸收法相符。对于w(Co)=0.82%的含钴分子筛测定8次,其RSD为134%。  相似文献   

6.
介绍了旋转薄膜蒸发器蒸馏富集水样中微量元素的原理及使用方法;对用感耦等离子体原子发射光谱测定微量Cd、Co、Cu、Cr、Ni、Pb、Ti、V和Y时,元素间的干扰问题进行了讨论。各待测元素微克级标准加入回收率为90%~108%,测定饮用水样的RSD(n=5)为0.66%~8.91%。  相似文献   

7.
X射线荧光光谱法直接测定地质样品中多种痕量元素   总被引:2,自引:0,他引:2  
邹海峰  苏克 《岩矿测试》1998,17(3):207-210
采用低压聚乙烯镶边垫底的粉末压饼法制样,X射线荧光光谱法直接测定了地质样品中痕量元素As、Ga、Sc、La、Y、Ce、W、Mo、Sn、Co和Pb。讨论了背景校正、谱线重叠校正、基体效应校正和仪器漂移校正等问题。利用理论α系数代替经验系数,使方法具有较高的准确度和较低的检出限。所测11个元素的检出限在(0.30~2.02)×10-6水平,精度(RSD,n=11)在0.95%~13.0%。方法经国家一级标准物质分析验证,结果与标准值相符。  相似文献   

8.
研究了邻硝基苯基萤光酮(o-NPF)-溴化十六烷基三甲铵(CTMAB)与W(Ⅵ)和Mo(Ⅵ)共同显色条件及其吸收光谱和导数光谱行为。选择二阶导数光谱用基线相交法同时测定W和Mo,对1:10或10:1的W和Mo互不干扰,回收完全。测定范围为4~160ng/ml的W,4~120ng/ml的Mo。对10 ̄(-6)水平的W和Mo测定的RSD(n=8)均小于10%,对国家一级地质标样测定结果符合要求。  相似文献   

9.
报道了用吡咯烷二硫代氨基甲酸铵(APDC)有机螯合沉淀剂沉淀富集后,等离子体质谱法测定地球化学样品中26个痕量元素的方法。研究了APDC定量沉淀待测金属离子的条件,分别在pH2和pH7时使26个元素富集,回收率在94%~105%;样品测定下限为0.01~0.4μg/g;方法的RSD(n=10)为3%~13%。经几种地球化学标准物质验证,结果与推荐值相符。  相似文献   

10.
研究了新合成的meso-四(2-磺酸萘基)卟啉(TNPS4)与Mn^2+的显色反应。在pH8.0的Na2B4O7-HCl缓冲溶液中,TNPS4与Mn^2+形成稳定的配合物,最大吸收波长470nm,配合物组成为TNPS4:Mn^2+=2:1,表观摩尔吸光系数ε=1.03×10^5L·mol^-1·cm^-1,线性范围0.0-5.0μgMn^2+/25ml。用于化探样品中Mn的测定,结果令人满意。  相似文献   

11.
胡钧 《上海国土资源》1999,(1):26-30,38
针对新颁国家标准,采用改进的测试技术,对桩基动力特性进行试验研究,取得不同类型基础所相应的测试方法,桩基动力特性参数主要影响因素等方面的结论。  相似文献   

12.
Near the outskirts of the Albanian port of Durres on the Adriatic Coast, at a place called Porto Romano, an old chemical complex has been producing chromate salts for a period of ∼20 years (1972–1993). As a result large quantities of chromite ore processing residue (COPR) waste were released mainly as suspended particles and/or dissolved species in effluents, which settled in a decantation pond area, 200 × 250 m in size, east of the industrial plant. Unfortunately, pollutants were spread out with time. Knowing that chromium mobility and toxicity in natural settings is species dependent, the species characterization has been carried out in different sampling media (pond sediments, lagoonal sediments and water samples). Five pond profiles were sampled within the decantation area up to a depth of ∼1 m, till the underlying Quaternary lagoonal silty-clays were reached. Total Cr content is highly variable with values between 1,130 and 24,409 mg/kg which is clearly higher than the defined local background values for lagoonal silty-clays (198 mg/kg of Cr). Leaching of Cr(VI) especially occurs in the pond sediments, which are low in OC, CEC and clay content, under acidic and neutral pH conditions (e.g. up to ∼2,230 mg/kg Cr(VI) leached from a sample containing a total concentration of Cr 12,200 mg/kg). Moreover, leaching of the Cr(III) occurs only under strictly acidic conditions (maximum 1,144 mg/kg leached from a sample containing a total Cr-concentration of 17,608 mg/kg). In this study also a number of natural attenuation conditions (i.e. reaction with lagoonal clays rich in organic matter and iron as well as isomorphous substitution) have been recognized.  相似文献   

13.
Character of the Si and Al Phases in Coal Gangue and Its Ash   总被引:1,自引:0,他引:1  
Abstract: Analysis of the Si and Al phases in coal gangue fuel and its ash is important for use of coal gangue ashes. A comprehensive study by theoretical and experimental analyses with differential thermal analysis, X-ray diffraction and Infrared Spectroscopy has been made in the present article to explore the diagram of the Si and Al phases in coal gangue fuel and its ashes. It is found that kaolinite and quartz are the main phases in coal gangue fuel. The ratio of moles Al2O3 to SiO2 (i.e., Al2O3 (mole) /SiO2 (mole)) is usually no more than 0.5 in most coal gangue fuel and its ashes. The kaolinit at about 984°C releases a large quantity of SiO2, which makes calcine coal gangue more active than coal gangue itself. The relationship between the ratio Al2O3 (mole)/SiO2(mole) and the components of coal gangue ash is analyzed, resulting in a formula to calculate the quantity of each phase. Applying the formula to the testing samples from an electric plant in north China supports the above conclusions.  相似文献   

14.
王长虹  朱合华  钱七虎 《岩土力学》2014,35(Z2):386-392
岩土参数的空间分布特征由于存在取样数据之间自相关和互相关的特性,未知点的岩土参数属性可通过特定的方法内插或外推,经典的数理统计方法难以确定周围的数据样本点以及相应的插值系数。首先介绍地统计学中基于距离加权的普通克里金(ordinary kriging, OK)算法、泛克里金算法(UK)和协克里金算法(CK)。由于基于滑动距离加权的OK算法无法度量局部空间的奇异性,将引入多重分形理论弥补该缺陷。以2010上海世博会的世博轴区域(长525 m,宽80 m)为工程背景,区域内共有42个取土钻孔,以典型的粉质黏土层3个重要的物理力学指标,即黏聚力、内摩擦角和压缩模量验证以上算法。对于岩土参数黏聚力和内摩擦角,预测精度由高至低为多重分形联合模型(MK)、协克里金模型(CK)、泛克里金模型(UK)、普通克里金模型(OK);对于岩土参数压缩模量,相应的顺序为泛克里金模型和普通克里金模型位置互换。研究结果证明,在岩土参数空间场的分析中,辅助信息有助于提高数据预测精度,并且多重分形联合模型有助于分析空间局部的奇异性。  相似文献   

15.
张翔  丁晶 《水科学进展》2000,11(1):105-110
从神经网络(NN),模糊系统(FS)和进化算法(EC)三者相结合的角度,介绍了神经智能信息处理系统的研究现状,讨论了该系统在水文水资源中的应用,并对其应用发展趋势进行了预测。  相似文献   

16.
在实验室条件下,选择几种有代表性的无机离子(包括宏观生命元素、微量生命元素、副生命元素),并保持一定的浓度和PH值(6.18±0.2),研究了各无机离子和烷化剂对DNATm值的影响。结果表明,有益元素与有害元素对DNATm值高低的影响明显不同。前者使Tm升高,抑制DNA热变性,后者使Tm值降低,促进DNA热变性;这并非阴阳离子的离子强度造成的,而是由于加入的无机离子对DNA分子中磷酸基因和碱基的作用不同所致。而且它们对DNATm值的影响幅度和方向与烷化剂的存在有很大关系。烷化剂可以大大降低Tm值,加入各种无机离子对烷化作用产生不同的影响。这表明,作为致癌的主要机理—烷化作用可能与各种离子的存在和在生物体内的平衡状态有关。所测结果还表明,烷化剂的作用比无机离子大得多。这些结果有助于区分有害与有益元素,对癌症的早期发现及阐明致癌、防癌机理有重要意义。  相似文献   

17.
Speciation of Cr and V within BOF steel slag reused in road constructions   总被引:1,自引:0,他引:1  
Basic Oxygen Furnace (BOF) steel slag is a residue from the basic oxygen converter in steel-making operations, which is partially reused as an aggregate for road constructions. It is essentially composed of calcium, silicon and iron but also contains potential toxic elements present as traces, like chromium (Cr, 2600 mg kg− 1) and vanadium (V, 690 mg kg− 1), which can be released. The linked results of chemical analysis, XRD and SEM-EDX enabled to identify the main mineral phases composing BOF slag and EDX micro-analyses indicated that V and Cr were associated to dicalciumferrite. A 47-days static leaching test at a laboratory scale with a controlled pH of 5 (pHstat leaching test) showed that Cr was little released, while V was significantly released. Finally, X-ray absorption near-edge structure (XANES) spectra of 3 BOF slag samples were recorded (“raw”, leached 47 days at pH 5 and aged 2 years in a lysimeter). XANES spectra showed that Cr is present at octahedral coordination in the trivalent form, the less mobile and less toxic one, and that its speciation does not evolve during natural ageing and leaching at pH 5. They also indicated that V is predominantly present in the + 4 oxidation state and seems to become oxidized to the pentavalent form (the most toxic form) during natural ageing.  相似文献   

18.
INTRODUCTION The properties of phosphor usedin a plasma dis-play panel (PDP) affect the performance of the PDP(Okazaki et al .,2000 ; Rao and Devine ,2000) . Theluminescent properties of the phosphor are decided bythe morphology ,particle size and size distribution ofthe powder ,sothe requirements for the powder mor-phology are high in a color PDP which belongs to ahigh resolution display apparatus (I m et al .,2005 ;Yang et al ., 2005) . Studies have shown that withsmall particle si…  相似文献   

19.
东南亚及哀牢山红河构造带构造演化的讨论   总被引:17,自引:1,他引:16  
张进江  钟大赉 《地质论评》1999,45(4):337-344
通过对东南亚和哀牢山红河构造带演化已有模式的分析,在近年来本区海上研究资料的了,结合滇西地质情况,认为东南亚的构造格局是由印度洋、太平洋和欧亚三大构造体系共同作用形成的。60 ̄15MaBP,欧亚构造体系分别与太平洋和印度洋构造体系作用在东南亚东、西部形成两个弧后盆地扩张体系。两体系扩张强度和方向的不同,形成转换调节构造带-哀牢山红河构造带。东部较强的扩张作用使扬子板块向北运动,形成哀牢山以东的逆冲  相似文献   

20.
The spatial sampling offered by TOPEX and Jason series of satellite radar altimeters and its continuity during the last twenty years are major assets to provide an improved vision of the global mean sea level (GMSL). The objective of this paper is to examine the recent GMSL variations (1993–2012) and to investigate the correlation between the GMSL and ENSO (El Niño-southern oscillation) episodes. For this purpose, a mean sea level anomalies time series, obtained from TOPEX, Jason-1 and Jason-2 measurements, is used to determine the trend of GMSL changes by using a simplified form of an unobserved components model (namely UCM). Then, to investigate the impact of the ENSO phenomenon on the GMSL changes, we considered the sea surface temperature anomalies (SSTA) index over the Niño3 region (5N–5S 150W–90W). Cross wavelet transform and wavelet coherence analysis are performed to expose common power between the GMSL changes and the SSTA index and their relative phase in the time–frequency space. The results indicate that there are in the estimated GMSL's trend a number of fluctuations over short periods that are least partly related to the El Niño/La Niña episodes. Cross wavelet transform and wavelet coherence analysis indicate that a significant correlation between GMSL and ENSO occurred during 1997–1998, 2006–2007, 2009–2010 El Niño events and 2007–2008 and 2010–2011 La Niña ones. All these areas show in-phase relationship, suggesting that GMSL and SSTA index vary synchronously.  相似文献   

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