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91.
本文研究了离子对反相液相色谱分析氨基酚异构体的可能性、影响因素和色谱条件,发现以含4×10-8mol/L四丁基碘化铵、0.184mol/L醋酸钠的甲醇水溶液(23:77)作为流动相,ODS为固定相时可以实现氨基酚异构体的良好分离。  相似文献   
92.
姚丹姝 《合成化学》1998,6(3):315-318
含活性基团的醛可与烯丙碘和锡粉直接进行亲核加成反应,得到高烯丙基的醇,水的存在不利于此反应的进行,与烯丙基溴相比,烯丙基碘反应活性更强,可在短时间内得较高的产率。  相似文献   
93.
The binding of wogonin to human serum albumin (HSA) has been studied by spectroscopic method including circular dichroism (CD), infrared spectra (IR) and fluorescence spectra. The fluorescence properties of HSA were examined in presence of wogonin and the fluorescence intensity of HSA was significantly decreased in the presence of wogonin. The binding parameters of wogonin were studied from the fluorescence decreasing of HSA by the fluoremetric titrations. The Stern-Volmer plots indicated that the binding of wogonin to HSA at 296, 303, 310 K is characterized by one binding site with the binding constant K(S-V) at 1.872 x 10(5), 1.561 x 10(5), 1.392 x 10(5), respectively, which are good agreement with the results from the Scatchard plots. The binding process was exothermic, enthalpy driven and spontaneous, as indicated by the thermodynamic analyses, and the major part of the binding energy is hydrophobic interaction, which were consistent with the result of molecule modelling study, and there are also a numbers of hydrogen bonds between wogonin and HSA. Furthermore, the displacement experiments indicate that wogonin can bind to the subdomain IIA, that is, the site I of HSA, which is also good agreement with the result of molecule modelling study.  相似文献   
94.
Photocatalytic ethane conversion into value-added chemicals is a great challenge especially under visible light irradiation. The production of ethyl hydroperoxide (CH3CH2OOH), which is a promising radical reservoir for regulating the oxidative stress in cells, is even more challenging due to its facile decomposition. Here, we demonstrated a design of a highly efficient visible-light-responsive photocatalyst, Au/WO3, for ethane oxidation into CH3CH2OOH, achieving an impressive yield of 1887 μmol gcat−1 in two hours under visible light irradiation at room temperature for the first time. Furthermore, thermal energy was introduced into the photocatalytic system to increase the driving force for ethane oxidation, enhancing CH3CH2OOH production by six times to 11 233 μmol gcat−1 at 100 °C and achieving a significant apparent quantum efficiency of 17.9% at 450 nm. In addition, trapping active species and isotope-labeling reactants revealed the reaction pathway. These findings pave the way for scalable ethane conversion into CH3CH2OOH as a potential anticancer drug.

Highly efficient visible-light driven photocatalytic oxidation of ethane into ethyl hydroperoxide was realized for the first time over Au/WO3.  相似文献   
95.
A kind of azo-containing resin (Azo-R) was synthesized by a simple way through the coupling reaction of 2-nitro-N-methyldiphenylamine-4-diazoresin (NDR) with phenol, and a new covalentely attached multilayer film from Azo-R as H-donor and photosensitive diazoresin, diphenylamine-4-diazoresin (DR) as H-acceptor via H-bonding attraction by selfassembly technique has been fabricated. Following the decomposition of diazonium group of DR under exposure to UV light, the H-bonds between the layers of the film convert to covalent bonds and the film becomes very stable toward polar solvents or electrolyte aqueous solutions. Thus the UV-irradiated azo-containing films can be used to measure photocurrent in a conventional three-electrode photoelectrochemical cell using KCl as supporting electrolyte. It was confirmed that the azo-containing multilayer film is responsible for the photocurrent generation.  相似文献   
96.
借助定量金相、扫描电子显微镜、透射电子显微镜等微观分析手段对钨质量分数为93%的钨合金在15~50GPa冲击压力下微观结构响应性态进行了考察,发现了一些钨合金所特有的现象,即钨颗粒与粘结相交界处出现成分迁移,新相析出;并结合断口分析,探讨了钨合金在冲击作用下发生断裂的微观特征与韧脆转化间的关系及其物理本质。  相似文献   
97.
This paper introduces an experiment about waste liquid recovery and effect evaluation in laboratory. Through this experiment, the basic operations of crystal preparation, chemical analysis and instrumental analysis are further consolidated. At the same time, it allows students to experience a series of possible problems of condition selection and control in the process of waste liquid treatment. We hope to improve the students' ability to analyze and solve problems, enhance their interest in learning, and strengthen their humanistic education.  相似文献   
98.
An easily prepared and highly efficient monodentate phosphoramidite ligand derived from BINOL, (S)-2,2'-O,O-(1,1'-binaphthyl)-dioxo-N,N-diethylphospholidine, was examined in the hydrogenation of both enamides and alpha-dehydroamino acid derivatives. The catalyst provided remarkably high enantioselectivities (up to 99.6% ee for enamides and >99.9% ee for alpha-dehydroamino acid derivatives).  相似文献   
99.
Hydrogen adsorption-desorption over Mo2N has been studied using a temperature-programmed technique. It is revealed that hydrogen on Mo2N exhibits very high mobility leading to migration of the surface hydrogen into the sublayer and bulk of the sample or the reverse. The surface hydrogen species are preferentially formed when adsorption is carried out below 573 K. On increasing the adsorption temperature to above 573 K, the quantity of hydrogen species located in the sublayer or/and bulk of the Mo2N sample increases significantly.  相似文献   
100.
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