首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 578 毫秒
1.
林霞  黄风华  陈娟  张慧 《化学研究》2010,21(3):85-87
通过CdSe/CdS/ZnS量子点与壳聚糖之间的静电作用,用共混法制备了壳聚糖-CdSe/CdS/ZnS复合物.用荧光光谱、紫外-可见光谱、红外光谱对所得的壳聚糖-CdSe/CdS/ZnS复合物进行了表征.研究结果表明:壳聚糖-CdSe/CdS/ZnS复合物具有良好的光学性能.  相似文献   

2.
The effect of temperature on the adsorption/desorption of ammonia from the air mixture on the surface of commercial binary V/Al and ternary Pd/V/Al, V(0.65 wt.%) /W(6.73 wt.%) /Ti and V(1.8 wt.%) /W(7.3 wt.%) /Ti de-NOx catalysts has been investigated by temperature-programmed desorption (TPD) method. The ability of the commercial catalysts to adsorb ammonia in the most stable surface species was shown to correlate well with their suppression of the NH3 oxidation.  相似文献   

3.
4.
5.
以玻碳电极为基底成功制备了聚L-苏氨酸poly(L-Threonine)/多壁碳纳米管(MCNTs)修饰电极(p-L-Thr/ MCNTs/GCE).研究了盐酸氯丙嗪在该修饰电极上的电化学行为.该修饰电极对盐酸氯丙嗪具有明显的电催化氧化作用,并对此电极进行显微表征.本研究将此修饰电极用于流动注射不可逆双安培(FL-IB)体系的构建,即利用盐酸氯丙嗪在p-L-Thr/MCNTs/GCE上的氧化和高锰酸钾(KMnO4)在另一支铂电极上的还原构建了双安培检测体系,成功的建立了在外加电压为0 V条件下流动注射双安培法直接测定盐酸氯丙嗪的方法.在0 V外加电压下,在1 mol/L pH6.8的磷酸盐缓冲溶液的载液中,氧化峰峰电流与盐酸氯丙嗪浓度在2.0×10-6mol/L~4.0×10-5 mol/L范围内呈良好的线性关系,其线性回归方程为i (nA)=9.73×107C-50(r=0.9993,n=6),在4.0×10-5mol/L~10-3 mol/L范围内呈线性关系,其线性回归方程为i (nA)=2.33×107C+4×103 (r=0.9984,n=7),方法检出限为4.0×10-7 mol/L (S/N=3).连续测定1.00×10-4mol/L的盐酸氯丙嗪标准溶液20次,电流值RSD为2.44%,进样频率为90样/h.该方法具有较高的选择性和灵敏度.对盐酸氯丙嗪片中的盐酸氯丙嗪的含量的测定,结果比较满意.  相似文献   

6.
Oxford University Press, Oxford 2008. 992 pp., hardcover $ 295.00.—ISBN 978–0195365818

  相似文献   


7.
8.
9.
载体对浸渍型Cu/Mn/Mg/K甲醇裂解催化剂的影响;  相似文献   

10.
A sensitive, selective, and reproducible in-tube solid-phase microextraction and liquid chromatographic (in-tube SPME/LC-UV) method for determination of lidocaine and its metabolite monoethylglycinexylidide (MEGX) in human plasma has been developed, validated, and further applied to pharmacokinetic study in pregnant women with gestational diabetes mellitus (GDM) subjected to epidural anesthesia. Important factors in the optimization of in-tube SPME performance are discussed, including the draw/eject sample volume, draw/eject cycle number, draw/eject flow rate, sample pH, and influence of plasma proteins. The limits of quantification of the in-tube SPME/LC method were 50 ng/mL for both metabolite and lidocaine. The interday and intraday precision had coefficients of variation lower than 8%, and accuracy ranged from 95 to 117%. The response of the in-tube SPME/LC method for analytes was linear over a dynamic range from 50 to 5000 ng/mL, with correlation coefficients higher than 0.9976. The developed in-tube SPME/LC method was successfully used to analyze lidocaine and its metabolite in plasma samples from pregnant women with GDM subjected to epidural anesthesia for pharmacokinetic study.  相似文献   

11.
PP/尼龙66/聚碳酸酯/ABS共混高聚物的SEM样品制作   总被引:1,自引:0,他引:1  
讨论了PP/尼龙66/聚碳酸酯/ABS共混高聚物的扫描电子显微镜样品制作中存在的问题,通过实验,探讨了出该材料最佳的样品制作条件。  相似文献   

12.
通过有机氮磷农药测定的样品前处理技术一圆盘固相萃取、GC/MS的测定技术—选择离子跳变扫描SIM的应用研究,建立了水体中有机氮磷的分析测定方法.其方法检出限达到了ng/L级的水平。  相似文献   

13.
以壳聚糖(CS)对SiO2进行表面修饰, 采用浸渍还原法制备了负载型Ni-B非晶态合金催化剂(Ni-B/CS/SiO2), 并采用XRD、FTIR、电感耦合等离子体发射光谱(ICP)、BET、XPS、TEM、SAED等表征方法研究了催化剂的非晶性质、原子组成、尺寸分布及粒径大小等. 考察了催化剂对糠醇加氢制四氢糠醇反应的催化性能, 并与没有壳聚糖修饰的Ni-B/SiO2催化剂及Raney Ni催化剂进行了对比. 结果表明, 加入壳聚糖制得的Ni-B/CS/SiO2催化剂的活性组分Ni-B团簇粒径更小, 表面活性组分浓度更高, 催化活性更高.  相似文献   

14.
15.
李娟  崔利 《应用化学》2011,28(3):297-301
在聚苯胺(PANI)和二氧化锰(MnO2)存在的条件下,以FeCl3/甲基橙为模板,通过化学氧化法聚合吡咯(Py)单体,制备MnO2/PPy/PANI纳米管复合材料。 利用X射线衍射、透射电子显微镜、红外光谱和电化学测试等多种测试技术对复合材料进行物性表征和电化学电容性能测试,并讨论了不同含量的PANI对复合物材料的结构和性能的影响。 结果表明,由于PANI、MnO2与PPy三者的相互协同作用,以及材料管状结构的大比表面积,使三元复合材料具有比二元复合材料要大的电化学活性。 所合成的三元复合材料最大比容量达到458.4 F/g。  相似文献   

16.
Chemical Vapor Transport of Intermetallic Systems. 11 Chemical Vapor Transport of Ternary Intermetallic Phases in the Systems Cr/Co/Ge and Co/Ta/Ge By means of chemical vapor transport using iodine as transport agent it is possible to prepare a number of ternary intermetallic compounds in the system Co/Cr/Ge as single crystals. The transport behaviour in this ternary system is related to that in the binary systems. Some informations are given about transport phenomena in the systems Co/Cr and Co/Ta/Ge.  相似文献   

17.
4种儿茶素类化合物电喷雾质谱裂解规律的研究   总被引:2,自引:0,他引:2  
利用离子阱飞行时间质谱仪的高质量精度、高分辨率及多级测定性能, 对儿茶素类化合物(二组对映异构体)质谱裂解进行研究, 并利用氢/氘交换法对裂解方式进行确证. 发现儿茶素对映异构体间具有相同的质谱裂解途径, 多级质谱无明显区别. 在二级质谱中, 表儿茶素/儿茶素(EC/C)丢失的CO2发生在A环, 丢失的C2H2O发生在B环. 1,4A-, 1,3A-, 1,2A-和[M-H-B环]-4个碎片离子为EC/C特征离子, 通过这4个离子质量数变化, 推测A环上的取代情况. 因表儿茶素没食子酸酯/儿茶素没食子酸酯(ECG/CG)结构上都含有没食子酸取代基, 在二级质谱中均可见m/z169特征峰, 此离子可用于ECG/CG和EC/C区分.  相似文献   

18.
An ultra-sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for the analysis of oral contraceptive ethinyl estradiol (EE) was developed and validated over the curve range of 2.5-500 pg/mL using 1 mL of human plasma sample. Ethinyl estradiol and the internal standard, ethinyl estradiol tetra-deuterated (EE-d4), were extracted from the plasma matrix with methyl t-butyl ether, derivatized with dansyl chloride and then back-extracted into hexane. The hexane phase was evaporated to dryness, reconstituted and injected onto the LC/MS/MS system. The chromatographic separation was achieved on a Luna C(18) column (50 x 2 mm, 5 micro m) with an isocratic mobile phase of 20:80 (v/v) water:acetonitrile with 1% formic acid. The offline derivatization procedure introduced the easily ionizable tertiary amine function group to EE. This greatly improved analyte sensitivity in electrospray ionization and enabled us to achieve the desired lower limit of quantitation at 2.5 pg/mL. This high sensitivity method can be used for therapeutic drug monitoring or supporting bio-equivalence and drug-drug interaction studies in human subjects.  相似文献   

19.
锂离子电池正极材料LiCo1/3 Ni1/3Mn1/3O2   总被引:2,自引:0,他引:2  
王希敏  王先友  罗旭芳  廖力 《化学进展》2006,18(12):1720-1724
镍钴锰三元材料作为锂二次电池正极材料是目前国内外研究热点。综述了三元材料近几年国内外的研究状况,重点介绍了LiCo1/3Ni1/3Mn1/3O2材料的结构与电化学性能的内在联系,探讨了不同制备方法及不同元素的掺杂改性对材料的影响,讨论了LiCo1/3Ni1/3Mn1/3O2正极材料的应用前景。  相似文献   

20.
Thermal Characterization of Materials Using Evolved Gas Analysis   总被引:1,自引:0,他引:1  
Thermal analysis combined with evolved gas analysis has been used for some time. Thermogravimetry (TG) coupled with Fourier transform infrared (FTIR) spectroscopy(TG/FTIR), Thermogravimetry (TG) coupled with mass spectrometry (TG/MS), and Thermogravimetry (TG) coupled with GC/MS offers structural identification of compounds evolving during thermal processes. These evolved gas analysis (EGA) techniques allow to evaluate the chemical pathway of the degradation reaction by determining the decomposition products. In this paper the TG/FTIR, TG/MS, and Pyrolysis/GC-MS systems will be described and their applications in the study of several materials will be discussed, including the analysis of the degradation mechanisms of organically modified clays, polymers, and coal blends. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号