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1.
应用自制的ECL-1型电致化学发光仪,对新试剂6-(2-羟基-4-二乙基氨苯偶氮)-2.3-二氢-1,4-酞嗪二酮(HDEA)在Na2CO3-NaHCO3缓冲介质中的电化学发光行为作了研究.结果发现,当介质pH值为 10.54时,在一定的实验条件下,施加 1.7V (VS.SCE)三角波脉冲电压,体系的发光强度与HDEA浓度在5.0 × 10-9~1.0×10-6mol/L范围内呈线性关系,反应的检测限达1.0×10-9mol/L.  相似文献   

2.
报道了一种反相HPLC方法对几种芳烃衍生物型捕收剂的分离和测定.该法借助色谱柱LiChroCART100RP18(5μm),流动相:甲醇-水-5%H3PO4-5%H2SO4(45∶55∶4∶0.5,体积分数)和紫外检测器在285nm波长下进行.在0.0005~0.01g/L浓度范围内,方法的相对标准偏差为1.1%~2.4%.水杨羟肟,苯并三唑,水杨醛肟,水杨酸,铜铁灵等的检出限分别为1.0×10-6,0.2×10-6,1.0×10-6,5.0×10-6和6.0×10-6g/L,所研制的方法已应用于矿物浮选过程实际样品的分析.  相似文献   

3.
螺旋藻富集铜锰的两个试验   总被引:9,自引:1,他引:8  
几组螺旋藻富金属元素的模拟试验证明,藻类对数期pH值由低向高递增(一般pH上升3~4个单位),Eh总是下降(一般100mV~200mV),藻对各种元素一般都有最适生长浓度,Cu2+为0.06×10-6~0.97×10-6,Mn2+为1.46×10-6~8.26×10-6,它们的富集系数因初始浓度差别而有不同,如Cu2+,初始浓度0.10×10-6时则富集系数为96.8,0.65×10-6时则为49.2,当在1.91×10-6时则为124.7;Mn2+,初始浓度为2.44×10-6时则富集系数为15.44,4.28×10-6时则为6.02,15.97×10-6时则为605.4;腐殖质具有极大的富集力,富集金属元素的途径主要有细胞吸收和吸附,藻类生长改变环境成盐沉淀、种种络合物以及迁移再沉淀等过程.  相似文献   

4.
采用海藻酸钙凝胶包埋法及海藻酸钙凝胶包埋与戊二醛化学交联相结合的固定化方法,制备了固定化谷氨酸脱羧酶膜,与CO2气敏电极偶联制成谷氨酸生物传感器。经测试,对谷氨酸的线性响应范围为(1.0×10(-2)~2.0×10(-4))mol/L,斜率为55.7mV,检测下限为2.3×10(-4)mol/L,稳态响应时间为(9~15)min。用包埋与交联相结合制得的传感器,其稳定性优于仅用包埋法制得的传感器。  相似文献   

5.
提出了表面活性剂增敏的碱性降解荧光法测定四环索新方法,四环素在0.5mol/LNaOH溶液中反应,生成强荧光降解物,加入十六烷基三甲基溴化铵后。四环素荧光强度增强150倍,浓度在9.0×10 ̄(-9)~1.0×10 ̄(-6)mol/L范围内荧光强度与四环素含量成正比。本法成功地用于尿液和血清中四环素的回收测定。  相似文献   

6.
依诺沙星的电化学研究   总被引:3,自引:0,他引:3  
依诺沙星在Britton-Robinson缓冲液(pH2.0~11.0)中产生两个极谱还原峰。两峰强烈地受溶液pH值的影响,峰Ⅰ(-1.IV~-1.5Vvs.SCE)对应于吡啶环的双电子还原,峰Ⅱ(1.5伏~-1.7伏vs.SCE)对应于羰基的还原。实验表明电极过程是受扩散控制的不可逆过程,并测定了n,a和D0的值。当PH=2.2时,峰Ⅰ的峰电流与依诺沙星的浓度在4.0×10-8~6.0×10-6mol/L之间有线性关系,检测限为2.5×10-8mol/L,可用于依诺沙星的检测。  相似文献   

7.
用热液法制备了NaxWO3,x为00018~00380,这是一类新的六方晶钨氧化合物.斜方晶钨酸钠酸化水洗,再进行热液脱水;当钠含量≥160×10-6时(质量分数),得到斜方晶WO3·13H2O单相,当钠含量≤40×10-6时,得到WO3·H2O单相,当钠含量在40×10-6~160×10-6之间则为两相混合物.斜方晶WO3·13H2O在290~420℃脱水得到六方晶hNaxWO3;继续升高温度在420~450℃恒温处理,则得到单斜晶mNaxWO3.  相似文献   

8.
大红枣试管苗生根及移栽的研究   总被引:6,自引:0,他引:6  
大红枣无根试管苗在不同种类,不同浓度生长素以及在两种生长素不同配比的综合作用下生根的数量和质量不同。IBA和NAA的生根效应相同,合适的浓度均为0.4×10-6。IBA0.2×10-6+NAA0.2×10-6能够有效地提高生根质量。IBA0.2×10-6浸泡移栽基质和IBA500×10-6蘸根15~20min两种扦插方法都能促进生根成活。在选择试管苗的移栽基质方面,以森林腐殖土∶砂=3∶1(体积比)或锯沫效果较好  相似文献   

9.
本文以银丝汞膜电极为工作电极,在0.10mol/LNaOH溶液中经100℃水浴加热20min后,用线性扫描伏安仪制作CEx的阴极还原曲线,其峰电位-0.75V(VSAg/AgCl),浓度在2.0×10-7~2.10×10-6molL-1;2.0×10-6~2.0×10-5molL-1范围内,峰高与浓度呈线性关系,其线性回归方程i(格)=1.286×106c-0.1504(r=0.9958,c:2.0×10-5~2.0×10-6mol/L);i(格)=1.23×106+0.7870(r:0.9973,c=2.0×10-6~2.0×10-7molL-1).方法应用于胶囊中CEx的含量测定并与药典法相比,结果基本一致.此外利用循环伏安等方法对其降解产物电化学行为进行初探,该体系属于准可逆吸附体系.  相似文献   

10.
报道一种经亚硝化后用极谱定量二苯胺的极谱测定方法。在0.2mol/LHAc-0.025mol/LH_2SO_4-4×10 ̄(-6)mol/LNaNO_2底液中,二苯胺的亚硝化产物有一良好的极谱还原波,峰电位为-0.61V(vs,SCE),峰高与二苯胺浓度在2×10 ̄(-7)~1×10 ̄(-5)mol/L范围内有线性关系(r=0.9999)。  相似文献   

11.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to  相似文献   

15.
Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications (up to 574.8 km/ h test speeds or 380 km/h commercial speeds) in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.  相似文献   

16.
17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.  相似文献   

19.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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