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11.
微波场中甲烷部分氧化制合成气 Ⅱ.Co/ZrO_2催化剂在微波场中的升温行为及催化活性 总被引:4,自引:0,他引:4
近年来,甲烷部分氧化制合成气(POM)的研究一直十分活跃[1,2].前文报道了用于甲烷部分氧化制合成气的镍基催化剂(Ni/La2O3)在微波场中的升温行为和催化活性[3],发现在达到相同的CH4转化率时,微波活化方式下的催化剂床层温度比常规加热低得多... 相似文献
12.
Spectroscopic characterization of effective components anthraquinones in Chinese medicinal herbs binding with serum albumins 总被引:2,自引:0,他引:2
Bi S Song D Kan Y Xu D Tian Y Zhou X Zhang H 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,62(1-3):203-212
The interactions of serum albumins such as human serum albumin (HSA) and bovine serum albumin (BSA) with emodin, rhein, aloe-emodin and aloin were assessed employing fluorescence quenching and absorption spectroscopic techniques. The results obtained revealed that there are relatively strong binding affinity for the four anthraquinones with HSA and BSA and the binding constants for the interactions of anthraquinones with HSA or BSA at 20 degrees C were obtained. Anthraquinone-albumin interactions were studied at different temperatures and in the presence of some metal ions. And the competition binding of anthraquinones with serum albumins was also discussed. The Stern-Volmer curves suggested that the quenching occurring in the reactions was the static quenching process. The binding distances and transfer efficiencies for each binding reactions were calculated according to the F?ster theory of non-radiation energy transfer. Using thermodynamic equations, the main action forces of these reactions were also obtained. The reasons of the different binding affinities for different anthraquinone-albumin reactions were probed from the point of view of molecular structures. 相似文献
13.
冠醚型电极对局部麻醉药响应功能的研究 总被引:3,自引:0,他引:3
用二苯并24-冠-8作为活性物质、邻苯二甲酸二(2-乙基)己酯为增塑剂制得PVC膜电极。电极对局麻药丁卡因、普鲁卡因和利多卡因具有能斯特响应,用于局麻药针剂的测定取得满意的结果。 相似文献
14.
乙醇-盐-水-5-Br-PADAP体系萃取分离测定钯 总被引:3,自引:0,他引:3
研究了在硫酸铵存在下 ,5 Br PADAP乙醇体系中Pd(Ⅱ )、Rh(Ⅲ )、Pt(Ⅳ )的萃取行为及乙醇溶液的分相条件 ,讨论了影响萃取率的各种因素 ,试验表明 ,室温下 ,一定 pH范围内 ,该体系中的Pd(Ⅱ )几乎可完全被乙醇相萃取 ,而Rh(Ⅲ )、Pt(Ⅳ )不被萃取或萃取率很低 ,从而可实现Pd(Ⅱ )、Rh(Ⅲ )、Pt(Ⅳ )混合离子的定量分离 ,同时建立了Pd(Ⅱ )的测定方法。乙醇相中Pd(Ⅱ ) 5 Br PADAP配合物表观摩尔吸光系数为 1.18× 10 5L·mol- 1·cm- 1,钯量在 0~ 9.6 0 μg/10ml范围内符合比耳定律 ,检出限为 0 .0 90 μg/10ml。用该法分离混合样和测定两种活性碳钯催化剂中钯 ,结果满意 相似文献
15.
In this study, we report the design and synthesis of a series of new simplified fumitremorgin C analogues. The preliminary biological study indicated some of these simplified fumitremorgin C might be developed into breast cancer resistance inhibitors. 相似文献
16.
本文研究了以玻碳电极为基体的1:12硅钼杂多酸根(SiMo_(12)O_(40)~(4-)简称12-MSA)修饰电极的制备及其电化学行为,将12-MSA电极应用于线性扫描伏安法测定天然水中可溶性硅酸盐,结果满意.硅浓度在8.0×10~(-7)~1.7×10~(-3)mol/L,相对标准偏差(n=7)为1.85%,加标回收率为98.2%~103.6%,SiMo_(12)电极具有优良的选择性和稳定性。 相似文献
17.
Accreditation and Quality Assurance - 相似文献
18.
Raman spectroscopic analysis of supersaturated aqueous solution of MgO.B2O3-32%MgCl2-H2O during acidification and dilution 总被引:1,自引:0,他引:1
Zhihong L Bo G Shuni L Mancheng H Shuping X 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(13):3125-3128
Raman spectra of supersaturated aqueous solution of MgO.B2O3-32%MgCl2-H2O during acidification/alkalization and dilution have been studied. The assignments of the recorded Raman shift are given. The main existing forms of polyborate anions and their interaction in borate aqueous solution have been proposed through spectroscopic analysis. The experimental results indicate that the higher concentration of cation are beneficial not only to the dissolution of boric acid but also to the polymerization of polyborate anions. The existing forms and interaction among them also depend on the concentration of boron and the pH value in solution. 相似文献
19.
本文报导了以玻碳电极为基体的1:12硅钼杂多阴离子薄膜化学修铈电极的制备及其电化学特性。并应用于导数伏安法测定。在4.0×10 ̄(-3)m0l/L(NH_4)_6MO_7O_(24)-6.8×10 ̄(-2)mol/LNa_3Cit-0.48mol/LNHO_3体系中,硅浓度在8.3×10 ̄(-7)~1.7×10 ̄(-3)mol/L范围内与峰电流呈良好线性关系,检测限为8.0×10 ̄(-7)mol/L。对可溶性硅(以SiO_2计)为245.05mg/L的黑液,稀释10倍后,取2.00mL平行测定9次,RSD为0.58%,加标回收率在97.3%~104.4%间。 相似文献
20.
In weakly acidic buffer medium, the interaction of amikacin with calf thymus DNA, yeast RNA and denatured DNA has been investigated by using resonance Rayleigh scattering (RRS) technique. The result shows that calf thymus DNA is capable of enhancing the RRS intensity of the amikacin, while yeast RNA and denatured DNA have very little enhancement effect. Based on the characteristics, a sensitive assay for detecting double-stranded DNA in the presence of denatured DNA and yeast RNA has been developed. The enhancement of the RRS signal is directly proportional to the concentration of double-stranded DNA in the range 0.02-12.0 μg ml−1 for calf thymus DNA and its detection limit (3σ) is 2.5 ng ml−1. The method shows a wide linear range and high sensitivity, and almost no interference can be observed from RNA, denatured DNA, amino acid and most of the metal ions. The trace amounts of nucleic acid in synthetic samples and practical samples are determined with satisfactory results. Therefore, the proposed method is promising for as an effect means for recognition in vivo and determination in situ of double-stranded DNA. 相似文献