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1.
研究了反相高效液相色谱法定量分析20.0%卞黄隆和乙草胺二元混配稻田除草剂有效成分的方法。色谱条件:迪马C18柱(250×4.6mm,5μm,),流动相为甲醇/水(90∶10,V/V),λ=230nm,流速:1mL/min;线性相关系数为0.9999,外标法定量。卞黄隆和乙草胺的平均回收率分别为99.29%,100.24%(RSD<0.75%)。结果表明该法简便、快速、精密、准确,可以为20.0%卞.乙稻田除草剂质量标准的制定提供科学依据。  相似文献   

2.
以苯并三噻吩共聚物(BTT-BTz)为给体材料,具有不同能级结构的富勒烯衍生物为受体材料,通过共混方式制备光敏薄膜,并研究受体材料的能级结构对光伏器件开路电压(Voc)、短路电流(Jsc)、填充因子(FF)和电池效率(PCE)的影响.结果表明:当IC60BA为电子受体材料时,器件的Voc=1.06V,但Jsc较低,使得PCE仅为1.49%;当PC60BM和PC70BM为受体材料时,Voc分别为0.86V和0.81V,但Jsc较高,使得PCE分别为3.22%和5.06%.  相似文献   

3.
采用高效液相色谱法测定乌头须根中准格尔乌头胺和宋果灵两种生物碱类化合物的质量比.用Zorbax Extend-C18(4.6 mm×250 mm ODS,5μm)色谱柱,以V(甲醇)∶V(w(三乙胺)=0.1%)=6∶4为流动相,流速为1.0 mL/min,检测波长220nm,柱温25℃.结果表明:在选择的色谱条件下,两种生物碱类成分可实现基线分离,且线性范围宽(0.1~10.0μg),r2=0.999 8;平均加样回收率分别为99.8%和99.3%,相对标准偏差(RSD)分别为1.49%,1.46%(n=6),质量比分别为57.0,110.0μg/g.  相似文献   

4.
以12-钼磷酸和吡啶为原料合成了一种电荷转移盐. 通过C,N,Mo和P元素分析和热重分析确定其组成为[C5H5NH]3[PMo12O40]·4.5H2O,各元素的质量分数分别为(括号内为理论值)C 8.82 %(8.42%),N 1.69%(1.96%),P 1.40%(1.45%)和Mo 52.98%(53.78%);采用红外光谱、紫外-可见漫反射光谱、 X射线粉末衍射和循环伏安法等分析手段对该化合物进行了表征. 结果表明所合成的新型电荷转移化合物的杂多阴离子保持Keggin结构特征;相对于H3PMo12O40·xH2O,[C5H5NH]3[PMo12O40]·4.5H2O中由于离域π键的存在,对紫外-可见光的吸收从紫外区拓展到可见光区,并且在波长为370 nm处出现新的吸收峰;其还原电位为0.21 V,较H3PMo12O40·xH2O的还原电位(0.32 V)低,故其还原能力增强.  相似文献   

5.
采用V(正己烷)∶V(丙酮)=97.5∶2.5混合溶剂提取茶叶样品中的氯氰菊酯和氰戊菊酯农药残留,选用氟罗里硅土/活性炭混合柱为色谱柱和V(石油醚)/V(乙酸乙酯)=9∶1为淋洗液的方法净化待测样品.在优化的流动相配比(V(乙腈)∶V(水)=74∶26)及流速(1.2mL·min-1)条件下,用配备HypersilODS柱、二极管阵列检测器的高效液相色谱仪进行了待测组分的分离和测定.实验证明茶叶样品中氯氰菊酯和氰戊菊酯添加标准的回收率分别为71.0%和76 0%,加标回收的相对标准偏差(RSD%,n=6)分别为2.5%和2.2%.本方法具有溶剂使用量少、净化效果好、操作简便、快速等特点,可用于茶叶中氯氰菊酯和氰戊菊酯的农药残留分析.  相似文献   

6.
为测定PELA微粒中胰岛素含量,建立反相高效液相色谱方法. 以Zorbax300SB-C18高效液相色谱柱分离;检测波长为220 nm;流动相组成为:V(H2O(含φ(TFA)=0.15%))∶V(CH3CN)=66∶34;保留时间为4.3 min. 结果在ρ(胰岛素)为10~200 μg/mL范围内,峰面积(A)与胰岛素质量浓度(ρ)成线性变化,其线性方程为:ρ=7.82×10-2A +9.88×10-2,相关系数r=0.999 95. 日内差和日间差分别为0.6%和0.7%. 当ρ(胰岛素)为60, 80和100 μg/mL时的回收率分别为(98.1±0.5)%, (99.6±1.5)%和(99.4±1.0)%(n=6). 测得胰岛素在PELA微粒中的包封率为(56.3±3.3)%(n=6).  相似文献   

7.
建立了同时测定亚贡(Smallanthus sonchifolius)叶中亚贡二萜酸A和C含量的方法.采用高效液相色谱-质谱法,多反应监测(MRM)模式,大黄素为内标,色谱柱:UltimateTM XB-C18(150mm×4.6mm,5μm);流动相:V(甲醇)∶V(0.5%醋酸水溶液)=90∶10;流速:1.0mL/min;柱温:25℃.亚贡二萜酸A和C的线性范围均为0.2~10.0μg/mL(r≥0.999),平均加样回收率(n=6)分别为96.6%和92.4%,相对标准偏差(RSD)分别为1.9%和3.2%.实验数据表明,该方法操作简单、准确,且重复性好,可用于亚贡叶的质量控制.  相似文献   

8.
采用溶胶 -凝胶技术 ,以Ti(C4H9O) 4 和V2 O5粉末为原材料制备了纳米结构的TiO2 -x(V2 O5) (x为V2 O5的质量分数 ,分别为 10 % ,2 0 % ,30 % ,10 0 % )复合薄膜 .采用原子力显微镜观察薄膜的表面形貌 ;使用UV VIS NIR分光光度计测量了复合薄膜在紫外 -可见光波段的透射率和反射率光谱 ,研究其光吸收特性 .实验结果表明 :复合薄膜具有纳米颗粒结构 ;随着V2 O5用量的增加 ,复合薄膜在紫外光区的吸收逐渐增加 ,(αhv) 1/ 2 与hv存在线性关系 ,光学带隙由纯TiO2 的 3.36eV减小为x =30 %时的 2 .83eV ,光学带隙与x满足Eg(x) =Eg(0 ) [Eg(1)-Eg(0 ) -b]x bx2 关系式 ;复合薄膜光吸收边缘红移起因于V2 O5复合后薄膜中定域态宽度的增加 .  相似文献   

9.
采用反相高效液相色谱法,以C18为色谱柱,用甲醇 体积分数为0.1%的三乙胺水溶液(V甲醇∶V三乙胺=90∶10)作为流动相,在250 nm波长下,同时测定阿-甲微乳剂中的阿维菌素和甲氨基阿维菌素苯甲酸盐(简称甲维盐)的质量含量.结果表明:阿维菌素和甲维盐的线性关系分别为0.024 0~0.240 0 g.L-1和0.040 0~0.400 0 g.L-1,回收率分别为95.47%~102.00%和95.68%~101.34%,相对标准偏差分别为0.68%~1.25%和0.43%~1.06%,该法达到了简便、快速、准确的目的.  相似文献   

10.
以二茂铁二甲酸、甘氨酸、酪氨酸和精氨酸为原料,通过多步反应,合成新的二茂铁-肽衍生物Boc-HN-Fca-Gly-Gly-Tyr-Arg-OMe(7)(Fca代表二茂铁氨基酸)和Boc-HN-Fca-Gly-Gly-Tyr-Arg-OH(8),对寡聚肽的合成进行研究;对合成产物进行红外光谱和氢核磁共振谱表征,并运用循环伏安(CV)方法对产物的电化学性能进行研究。研究结果表明:产物(7)和(8)的产率分别为83.5%和80.2%;Boc-HN-Fca-Gly-Gly-Tyr-Arg-OMe的循环伏安扫描结果是氧化峰和还原峰电位分别为0.385V和0.346V,峰电位之差ΔEp为41 mV,峰电流密度之比Jpa/Jpc为1.055;对于Boc-HN-Fca-Gly-Gly-Tyr-Arg-OH,其氧化峰和还原峰电位分别为0.532V和0.453V,峰电位之差ΔEp为79mV,峰电流密度之比Jpa/Jpc为0.928。  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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