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111.
Ru(bpy)_(3~(2 )) electrochemiluminescence (ECL) was applied to determination of rutin. ECL intensity of Ru(bpy)_(3~(2 ))could be enhanced in the presence of rutin in basic solution on platinum electrode. At pH 9.9, light emission intensity was found to be linear with rutin in the range of 1-50 mmol/L.  相似文献   
112.
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   
113.
以PEG作相转移催化剂,在无机碱(K_2CO_3或Na_2CO_3)存在下,用乙基氯化物(O,O-二乙基硫代磷酰氯)与不同的胺反应,合成了六种N-取代硫代磷酰胺二乙酯,其结构经IR、NMR和元素分析证实。  相似文献   
114.
Non-negative matrix factorization(NMF)is a technique for dimensionality reduction by placing non-negativity constraints onthe matrix.Based on the PARAFAC model,NMF was extended for three-dimension data decomposition.The three-dimension non-negative matrix factorization(NMF3)algorithm,which was concise and easy to implement,was given in this paper.The NMF3algorithm implementation was based on elements but not on vectors.It could decompose a data array directly without unfolding,which was not similar to that the traditional algorithms do.It has been applied to the simulated data array decomposition andobtained reasonable results.It showed that NMF3 could be introduced for curve resolution in chemometrics.  相似文献   
115.
低硫可膨胀石墨的制备   总被引:18,自引:0,他引:18  
低硫可膨胀石墨的制备宋克敏,路文义,高淑英,阎秋燕(河北教育学院石家庄050091)关键词低硫可膨胀石墨,制备,过氧化氢,硫酸柔性石墨具有耐高温、耐酸碱、抗拉、抗压、抗辐射、回弹性等优良性能,被广泛应用于化工、机械、肮天、原子能等领域。但其原材料可膨...  相似文献   
116.
本文研究了氧化三甲胺Me3NO与羰基簇合物M4(CO)12-nLn(M=Co,Ir;n=1,2;L=磷配体)的氧转移反应动力学,讨论了反应机理。反应符合二级速率方程:r=K2[Me3NO][M4(CO)12-nLn]M4(CO)12-nLn的氧转移反应活性呈现如下顺序:中心元素不同时Co4(CO)12-nLn<Ir4(CO)12-nLn;取代配体不同时M4(CO)12-n(P(OMe)3)n>M4  相似文献   
117.
Rational manipulation of supramolecular structures on surfaces is of great importance and challenging. We show that imidazole-based hydrogen-bonded networks on a metal surface can transform into an isostructural coordination network for facile tuning of the pore size and guest recognition behaviours. Deposition of triangular-shaped benzotrisimidazole (H3btim) molecules on Au(111)/Ag(111) surfaces gives honeycomb networks linked by double N–H⋯N hydrogen bonds. While the H3btim hydrogen-bonded networks on Au(111) evaporate above 453 K, those on Ag(111) transform into isostructural [Ag3(btim)] coordination networks based on double N–Ag–N bonds at 423 K, by virtue of the unconventional metal–acid replacement reaction (Ag reduces H+). The transformation expands the pore diameter of the honeycomb networks from 3.8 Å to 6.9 Å, giving remarkably different host–guest recognition behaviours for fullerene and ferrocene molecules based on the size compatibility mechanism.

A hydrogen-bonded network on a Ag(111) surface can transform into an isostructural Ag(i) coordination network, giving drastically different host–guest recognition behaviours.  相似文献   
118.
The binary phase diagram of KNO3-KClO3 is studied by means of differential scanning calorimetry (DSC) and high-temperature X-ray diffraction. The limited solid solutions, K(NO3)1−x(ClO3)x (0<x<0.20) and K(NO3)1−x(ClO3)x (0.90<x<1.0), were formed in the KNO3-based solid solutions and KClO3-based solid solutions phase, respectively. For KNO3-based solid solutions, KNO3 ferroelectric phase can be stable from 423 to 223 K as a result of substituting of NO3 by ClO3-radicals. The temperatures for solidus and liquidus have been determined based on limited solid solutions. Two models, Henrian solution and regular solution theory for KNO3-based (α) phase and KClO3-based (β) phase, respectively, are employed to reproduce solidus and liquidus of the phase diagram. The results are in good agreement with the DSC data. The thermodynamic properties for α and β solid solutions have been derived from an optimization procedure using the experimental data. The calculated phase diagram and optimized thermodynamic parameters are thermodynamically self-consistent.  相似文献   
119.
CuO/活性炭和Fe2O3/活性炭催化还原NO   总被引:4,自引:0,他引:4  
高志明  赵震 《应用化学》1996,13(4):77-79
CuO/活性炭和Fe_2O_3/活性炭催化还原NO高志明,赵震,杨向光,吴越(中国科学院长春应用化学研究所长春130022)关键词活性炭,还原,NO,氧化铜,氧化铁目前,对固定源的NO处理是采用V2O5/TiO2作催化剂,NH3作还原剂的选择催化还原方...  相似文献   
120.
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