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1.
采用电位放电技术研究孔雀石绿(MG)增感顺式聚苯乙炔(ct-PPA)光导体的光敏性,发现孔雀石绿是顺式聚苯乙炔新的有效增感剂。以Al/ct-PPA:MG:PC(100:5:10)(1~1.5μm)/PVK:TPA:PC(10:10:1)(15~20μm)构成的光导体显示好的光敏性:表面接受电位,Vmax>700V;残余电位,Vmin<50V;暗衰速率,RD<10V/s;光衰放电量,△Vt>50%(1.0s);半衰时间,T12=0.87S;感光灵敏度,S=2.3×10-3(1x.s)-1,较未增感PPA光导体有较大的提高。MG对PPA为光谱增感  相似文献   

2.
研究建立了氢化物发生-冷阱捕获-色谱分离-原子吸收方法测定天然水中四种主要砷形态,测试系统自行组装,色谱柱填料采用ChromosorbGAW-DMCS(粒径0.3~0.45mm),其上涂布3%OV-101。方法的检出限以砷计分别为:As(V)0.51ng,As(Ⅲ)0.43ng,MMA0.38ng,DMA0.67ng;12ng砷标准偏差为As(Ⅴ)4.21%,As(Ⅱ)3.56%,MMA3.23%  相似文献   

3.
郑发鲲  张汉辉 《结构化学》1998,17(6):463-470
标题两个化合物是在反应体系(NH4)3VS4/CuX/PPh3/NEt4X中采用低温固相反应方法得到的,单晶X射线结构分析表明:VS4(CuPPh3)5Br2(I)和VS4-(CuPPh3)5I2是同构的,其中晶体属于单斜晶系,空间群P21c,Mr=1968.2,a=20.215(7),b=15.691(4),c=27.345(9)A,β=95.29(3)°,V=8637.0A^3,Z=4,Dc=  相似文献   

4.
双金属杂原子分子筛CrCoBEA的合成、波谱及催化性能研究   总被引:4,自引:0,他引:4  
采用水热晶化法首次合成出BEA结构含铬、钴,双金属杂原子分子筛CrCoBEA,对晶化时间,晶化温度,成胶配比等合成条件进行了优化研究,采用XRD,FTIR,UV-VisDRS,ESR及催化反应等方法测试其物相、波谱性质和催化性能,结果表明物质的量比为TEOS:0.017「Cr(acac)3」:0.017「Co(acac)3」:(0.58-0.64)TEAOH:0.01Al(NO3)3:(16-20  相似文献   

5.
铂—钯共显色衍生络合物的高效液相色谱研究   总被引:1,自引:3,他引:1  
张孝松  屈建 《分析化学》1993,21(12):1365-1369
研究了Pd(Ⅱ)和4,4'-二(二乙氨基)苯硫酮(BDPTK)共显色所生成的Pt(Ⅱ)络合物,于Nucleosil C8柱上,用含3×10^-3mol/L CSA和0.02mol/L HAc-NaAc(pH3.5)的乙腈-丙酮-水(72:5:23,V/V)作流动相(1.0ml/min)分离并检测。Pt的校正曲线的线性范围为0.2~3.0μg/ml,Pt检测限为0.7ng。此方法已应用于抗癌药物顺铂  相似文献   

6.
高效液相色谱法测定血清中茶碱浓度   总被引:2,自引:0,他引:2  
采用高效液相色谱,分析柱:3μm,3.3cm*4.6mm,I.D(Perkin Elmer,USA);预柱:10μm,1cm*2.1mm,I.D(Perkin ELmer,USA);以乙酰氨基酚为内标对氯仿-异丙醇(95:5,V/V)提取样品进行了分析,流动相:0.1mol/L醋酸缓冲液(PH=4.5)-甲醇(70:30,V/V);检测波长:270nm;流速0.5mL/min,3min即完成一次茶  相似文献   

7.
张洁辉  郑邦乾 《合成化学》1997,5(3):311-316
以二乙烯苯和双丙烯酸多缩乙二醇酯为交联剂、聚醋酸乙烯酯(PVAc)或它与醋酸丁酯(BAC)的混合物为致孔剂、BPO为引发剂,用悬浮聚合随后水解的方法制得了部分水解聚(丙烯酸甲酯-醋酸乙烯酯-甲基丙烯酸甲酯)[HP(MA-VAc-MMA)]多孔载体,研究了PVAc及(PVAc+BAC)用量、分子量及混合比对HP(MA-VAc-MMA)孔结构的影响。结果表明,当PVAc的M>2.5×105,PVAc/BAC为2.3,用量为10~20%时,可制得孔隙率较高,孔径分布较窄,孔表面积较大的多孔载体。这种载体适用于微生物固定化。  相似文献   

8.
作以新研制的4-(6-甲基-2-苯并噻唑偶氮)间苯三酚为柱前衍生试剂,用含10mmol/L的pH6.80的HAc-NaAc缓冲溶液,10mmol/L TBA.Br和1×10^-4mol/LEDTA的甲醇-水溶液(78:22,V/V)作流动相,在C18柱上,11min内反相HPLC分离测定了Cr(Ⅵ),V(Ⅴ),Co(Ⅱ),Ni(Ⅱ)。当S/N=3时,其检出限分别是V(Ⅴ)5.45ng,Co(Ⅱ)  相似文献   

9.
报道了用高效液用色谱法同时测定食用植物油中的抗氧剂叔丁基对羟基茴香醚(BHA)和2,6-二叔丁基对甲酚(BHT)的实验方法。采用ZorbaxODSC_(18)色谱住,甲醇:水(90:10,V/V)作流动相,检测波长为245nm,流速为1mL/min。检测下限分别为15ng(BHA),90ng(BHT),回收率分别是96.8%±9.8%(BHA),99.0%±3.2%(BHT)。方法快速、准确,灵敏度高。  相似文献   

10.
以Philips-VanVechten理论和晶体光学性质为基础,计算了LaX(X=N,P,As,Sb)晶体的离子半径(单位:nm):(La:N)为(0.1414,0.1236),(La:P)为(0.1518,0.1489),(La:As)为(0.1536,0.1526),(La:Sb)为(0.1586,0.1651).用LMTO-ASA方法对LaX系列晶体的能带结构进行了计算.所得到的能隙是:LaN为2.30eV,LaP为2.05eV,LaAs为1.66eV,LaSb为1.34eV.与实验结果相符.这也证明了作者得到的半径的合理性.  相似文献   

11.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

14.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.  相似文献   

17.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

18.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

19.
An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6ag and imidazo[1,5-a]quinoxalines 7ah by the reaction of 2-imidazolyl anilines 4ac with aryl aldehydes 5ak under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4ab was found to be instrumental for the success of the reaction.  相似文献   

20.
The Diels-Alder reactivity of 1,2-heteroborines (H4C4B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.  相似文献   

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