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1.
本文研究了溴化十二烷基二甲基苄铵-溴百里酚蓝与阴离子表面活性剂显色反应的适宜条件结果表明,在pH7.4~8.2范围内阴离子表面活性剂与题示试剂形成1:2:1的绿色离子缔合物,其最大吸收峰位于614nm处。表观摩尔吸光系数分别为ε^SDBS614=3.99×10^4L.mol^-1.cm^-1;ε^SDS614=3.70×10^4L.mol^-1.cm^-1,ε^SLS614=1.71×10^4L.  相似文献   

2.
鸟嘌呤—铜配合物在汞电极表面上的电吸附性的研究   总被引:1,自引:0,他引:1  
在0.02mol/L NaHCO3-0.05mol/La2SO4介质中、用极谱法和伏安法研究表明,铜-乌嘌呤配合物在汞电极表面上的吸附服从Langmuir吸附,测得其饱和吸附量Γm=1.1×10^-10mol/cm^2,吸附系数β=4.7×10^4,吸咐自由能△G°=-36.6kJ/mol。在8×10^-6mol/L Cu^2+离子存在下,可用示差脉冲阴极吸附溶出法测定8×10^-10~1×10^  相似文献   

3.
吴绍祖  方文焕 《分析化学》1995,23(11):1247-1251
本研究了一个高灵敏的测定镉的方法,离心光度法,该体系络合物λmax=560nm,表观摩尔吸系数ε560=5.06×10^8L.mol^-1.cm^-1,Cd^2+浓度0.10×10^-2-1.0×10^-2μg/10mL呈线性关系,本法已用于血清和水中痕量镉的测定,探讨了高灵敏的显色反应机理。  相似文献   

4.
马会民  黄月仙 《分析化学》1996,24(2):208-212
7-(对甲酰基苯偶氮)-8-羟基喹啉-5-磺酸是一新显色剂,该试剂在微碱性介质中(pH=7.5)与镓形成黄色络合物,络合物λmax=392nm,摩尔吸光系数ε392=2.24×10^4L.mcl^-1.cm^-1,同时在500nm呈现负峰,用双峰双波长法测定镓ε392-500=6.89×10^4L.mol^-1.cm^-1,灵敏度是单波长法的三倍多,线性范围0~2.0×10^-6mol/L。用拟定  相似文献   

5.
提出一种新的HRP底物-硝基磺酚S,初步探讨了在HRP催化下被过氧化氢氧化的机制,以硝基磺酚S为底物测定了酶促反应动力学常数Km和Ks分别为4.51×10^-5mol/L和28.1mol/L·s^-1。分别用于酶联免疫显色光度法和伏安酶联免疫分析法测定了IgG-HRP,其所能测定的最高稀释比分别为1:1.6×10^5和1:4.8×10^5。  相似文献   

6.
刘虹 《分析化学》1995,23(9):1077-1080
本研究了新试剂7-(2,4,6-三羟基苯偶氮)-8-羟基喹啉-5-磺酸与锆、铪的显色反应。酸性条件下锆、铪均可形成M-THBAQS-CTMAB三元络合物,ε^Zr515nm=3.27×10^4,ε^Hf515nm=3.8×10^4,适量H2O2使锆络合物吸光度显降低,据此实际了锆铬的同时测定。  相似文献   

7.
钨与溴邻苯三酚红—罗丹明6G协同显色的研究及其应用   总被引:3,自引:0,他引:3  
本文研究了聚乙二醇辛基苯基醚存在下,在硫酸介质中,钨与溴邻苯三酚红和罗丹明6G双试剂协同显色反应,反应结果形成红色络合物,最大吸收波长578nm,表观摩尔吸光系数4.41×10^5L.mol^-1.cm^-1。钨量在0-8μg/25ml范围内符合比尔定律。  相似文献   

8.
陈建荣  吴香梅 《分析化学》1994,22(9):928-930
本研究了1-(5-溴-2-吡啶偶氮)-2-萘酚-6-磺酸(5-Br-PAN-S)与铁(Ⅱ)的显色反应,试验表明,在pH3-10范围内铁(Ⅱ)与5-Br-PAN-S型成稳定的络合物,络合物在550nm和750nm有二个吸收峰,其表现摩尔吸光系数分别为2.31×10^4和1.77×10^4L.mol^-^1.cm^-^1。络合物组成比为铁(Ⅱ):5-Br-PAN-S=1:2,络合物稳定常数为1.82  相似文献   

9.
酶联免疫吸附法直接测定血清雌二醇   总被引:20,自引:0,他引:20  
金声  郭振泉 《分析化学》1994,22(2):115-120
本合成了3种不同载体蛋白的雌二醇抗原,研究了载体蛋白免疫原性对雌二醇抗体产生的影响。应用酶联免疫吸附分析法测定了血清中雌二醇,浓度范围为5-160ng/ml(1.8×10^-^8-5.9×10^-^7mol/L).RSD%小于10.%,检测限为1.97ng/ml,相当于98.5pg/孔(按空白平均值的二倍标准偏差计算)。另外,本还建立了一种用考马斯亮蓝G-250测定半抗原与蛋白结合比的方法,提  相似文献   

10.
顾慰中 《分析化学》1997,25(3):308-310
报道了复MoS62-4在铜表面形成不溶性族合物膜的性质,研制了一种簇合物膜亚硫酸根离子选择电极。电极对HSO^-3的线性响应范围为1×10^-4-1×10^-1mol/L;检测限为8×10^-5mol/L;响应斜度为58.5mV/dec;适宜的pH范围为9-10。  相似文献   

11.
综述了一种建立在表面作用力孔流通模型基础上计算高分子多孔滤过膜孔径大小及分布的方法。  相似文献   

12.
Experimental data on the equilibrium adsorption of sulfur hexafluoride, methane, carbon dioxide, and benzene on carbon adsorbents of different porosity obtained in a wide pressure range at 298–408 K were analyzed. The adsorption volumes, surface areas, and sizes of slit-shaped pores of the carbons were determined using several independent methods. A method for determination of the adsorption volume from the experimental isotherm of excessive adsorption of gases and the total content equation was proposed. The resulting values are similar to the adsorption volumes calculated from the data for vapors. A new method for the calculation of the adsorbent surface area is described. The method is based on the dependence of the adsorption volume of adsorbent pores on the effective size of adsorbate molecules. A possibility to determine the average size of narrow slit-shaped carbon pores from the difference of the initial heats of adsorption of the gas under study on the carbon black and porous carbon adsorbent is considered. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2219–2227, October, 2005.  相似文献   

13.
ZSM-5沸石膜内孔结构的研究   总被引:1,自引:0,他引:1  
以正丁胺 (NBA)为模板剂、利用水热法在α -Al2 O3载体管上成功地合成了ZSM - 5沸石膜。对合成的沸石粉末及沸石膜进行热重分析 ,结果表明ZSM - 5沸石粉末孔道中的模板剂在 390℃和 550℃下分解最快。对膜在不同的焙烧温度下 ,单组份气体N2 、H2 、n -C4 H10 、i-C4 H10 的渗透通量进行了测量 ,结果表明在焙烧过程中 ,膜内主要有两种不同的孔产生 ,低温下晶间孔内的水份和模板剂首先逸出 ,这些孔对气体的选择性不大 ,但它们所占比例也不大。高温下沸石膜的晶内孔相继打开 ,膜的渗透选择性也随之提高。 60 0℃以后 ,膜内孔基本全部打开 ,膜对气体的理想选择性也达到最大。  相似文献   

14.
15.
金属-有机框架材料在气体吸附/分离方面具有广泛的应用, 因而引起国内外学者的广泛关注。本文以6种代表性的MOFs为例简单介绍了利用理论工具研究MOFs孔结构的方法。  相似文献   

16.
This paper presents chiefly a classification of the loess pores in the Loess Platcau according to their origin and size and deals with the characteristics of different sorts of pores and their distributional regularities in regions and loess layers of various ages. The relationship between various pores and collapsibility is also discussed in the paper. We come tto a conclusion that the supporting openings are one of the important factors causing the subsidence on wetting because of their looseness and unstability.  相似文献   

17.
金属-有机框架材料孔结构的初步理论评估   总被引:1,自引:1,他引:0  
金属-有机框架材料在气体吸附/分离方面具有广泛的应用,因而引起国内外学者的广泛关注。本文以6种代表性的MOFs为例简单介绍了利用理论工具研究MOFs孔结构的方法。  相似文献   

18.
用双重孔模型计算变换催化剂内扩散效率因子   总被引:2,自引:0,他引:2  
本文将双重孔模型应用于WB~2、B109变换催化剂多组分反应系统内扩散效率因子的计算,并与平行交联孔模型进行比较。对WB-2加压变换催化剂用双重孔模型计算,计算值与实验值相对偏差在3.86%~53.94%;对B109变换催化剂,计算值与实验值偏差在-28.24%~-3.31%。  相似文献   

19.
A porous structure is the key factor to successful chromatography separation. Agarose gel as one of the most popular porous media has been extensively used in chromatography separation. As the cooling process in the agarose gelation procedure can directly influence the pore structure, ten kinds of 4% agarose media with different cooling rates from 0.132 to 16.7°C/min were synthesized, and the pore structure was determined accurately by using low‐field NMR spectroscopy. The curves of pore structure and cooling rate can be divided into two stages with the boundary of 6°C/min. In stage I, the pore structure met a power equation with the decrease of the cooling rate, and in stage II, the process reached a plateau. Confirmatory experiments proved that, by adjusting the cooling rate, a precise control of the pore structure of agarose media can be realized, furthermore, cooling rate optimization was an effective way to control the pore size of agarose media and can further tailor the pore structure for more effective separation of different proteins.  相似文献   

20.
Water vapor adsorption equilibria on activated carbons typically exhibit hysteresis. The size and shape of the hysteresis loop which separates the adsorption and desorption branches is a strong function of the pore size and interconnectivity of the pores. Neither conventional pore filling models nor statistical thermodynamics approaches provide a means for predicting the extent of hysteresis from only adsorption measurements. This work uses the Kelvin Equation in conjunction with the structural concept of a stochastic pore network to describe measured water isotherms on BPL carbon. Using a pore segment distribution function determined from the adsorption branch, it is shown that totally random assemblies underestimate the extent of hysteresis. It is possible, however, to closely fit the measured BPL-water hysteresis loop using a patchy heterogeneity in which a proportion of the larger pores are preferentially located on the exterior, mid-range pores are concentrated in a sub-surface layer and some large pores form shielded voids behind much smaller pores.Nomenclature p vapor phase partial pressure of sorbate - p sat saturation vapor pressure of sorbate - R gas constant - r pore radius - T absolute temperature - t adsorbed layer thickness - V L molar volume of adsorbed phase - surface tension - contact angle  相似文献   

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