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101.
潮州老香黄、老药桔中矿物质元素的测定 总被引:1,自引:0,他引:1
潮州老香黄、老药桔是潮州凉果特产中的极品,但对于这两类凉果的研究工作却很少。用火焰原子吸收法测定了老香黄、老药桔中锌,锰,镉,钙,铜,镍,钴等微量元素的含量。本结果可供生产商作参考,以便对某些含量过高的有害元素在生产过程进行有效的控制,也可作为营养分析的参考依据,为其产品的进一步开发提供科学依据。 相似文献
102.
Photocatalytic decolorization of methyl orange solution with potassium peroxydisulfate 总被引:1,自引:0,他引:1
Zhong Junbo Ma Di Zhao Hong Lian An Li Min Jiao Huang Shengtian Li Jianzhang 《Central European Journal of Chemistry》2008,6(2):245-252
Increasing environmental pollution caused by toxic dyes due to their hazardous nature is a matter of great concern. It has
been generally agreed that methyl orange (MO) can be effectively degraded in aerated K2S2O8 homogeneous reaction system using near-UV irradiation. In this paper photocatalytic degradation of MO solutions with K2S2O8 was investigated, with particular attention on the possible underlying mechanisms. This report has shown decolorization efficiency
of MO increases with the increasing of the dosage of the catalyst. There is no optimal amount of catalyst in our case, where
special attention was paid on the nature of the photocatalyst itself. The current research revealed that the decolorization
reaction is a pseudo first-order reaction when the concentration of MO is below 20 mg L−1 and the decolorization reaction is zero-order reaction when the concentration of MO is above 100 mg L−1, but the Langmuir-Hinshewood kinetic model does not describe this. The influence of IO4−, BrO3− and H2O2 were investigated in detailed. Several observations indicate that the mechanism is not involved in hydroxyl radical attacks
in MO degradation with K2S2O8 by UV irradiation. The possible underlying mechanisms are direct oxidation of the MO by S2O82− and hydrogen attraction by SO4•−.
相似文献
103.
三维大孔TiO2光催化剂的制备及其催化性能 总被引:3,自引:0,他引:3
以聚甲基丙烯酸甲酯微球为模板,以钛酸正丁酯为原料,采用溶胶-凝胶法制备了具有三维结构的大孔TiO2. 采用差示扫描量热、热重-微分热重、X射线衍射、红外光谱、扫描电子显微镜和氮气吸附等手段对样品进行了表征. 结果表明,高温热处理后得到的三维大孔TiO2光催化剂的孔径为200 nm左右,孔径分布均匀, TiO2纳米晶粒中锐钛矿相和金红石相的含量分别为82%和18%. 光催化氧化实验表明,此种三维结构的TiO2对甲基橙溶液具有较好的光催化氧化性能. 相似文献
104.
105.
Mohammad Rahimizadeh Mehdi Pordel Mehdi Bakavoli Zahra Bakhtiarpoor Ala Orafaie 《Monatshefte für Chemie / Chemical Monthly》2009,140(6):633-638
Abstract New imidazo[4,5-a]acridone derivatives were synthesized from the rearrangement of 3H-imidazo[4′,5′:3,4]benzo[c]isoxazoles. New imidazo[4,5-a]acridines were obtained from the reaction of imidazo[4,5-a]acridones in boiling POCl3. All of these compounds exhibited antimicrobial activities comparable to streptomycin as reference drug.
Graphical abstract
相似文献
106.
Lab-on-valve for the automatic determination of the total content and individual profiles of linear alkylbenzene sulfonates in water samples 总被引:1,自引:0,他引:1
Methods for the total content and individual determination of linear alkylbenzene sulfonates (LAS) in water samples based on the use of a lab-on-valve (LOV) module alone or coupled to CE equipment, respectively, have been developed. The total content of LAS has been determined by intrinsic absorption measurements (DA method) and after reaction with a methyl orange-cetylpyridine chloride mixture (MO method) with detection limits (LODs) of 21 ng/L and 15 microg/L, respectively, quantification limits (LOQs) of 70 ng/L, 50 microg/L, and development times of 100 and 124 s, respectively. The method for individual separation-quantification of LAS at very low concentration is based on automatic SPE preconcentration in the LOV module coupled on-line with the CE equipment. The LODs and LOQs thus obtained range between 1-21 and 4-70 ng/L, respectively, with linear dynamic ranges from the LOQ to 10 microg/L. Preconcentration factors of 10,000 and high efficiency to eliminate interferents by SPE enable application of the method to treated effluent, waste, surface and sea waters. 相似文献
107.
108.
The study of the partitioning mechanism of methyl orange in an aqueous two-phase system 总被引:2,自引:0,他引:2
An aqueous two-phase system of dodecyl triethylammonium bromide (C12NE, cationic surfactant) and sodium dodecyl sulfate (SDS, anionic surfactant) mixture is proposed for the extraction of some dyes and porphyrin compounds. Transparent two phase-systems are formed when the surfactant concentrations and C12NE/SDS ratios are in certain regions. In this study, the aqueous two phase-systems were prepared by mixing 0.1 mol l−1 C12NE and SDS with a molar ratio of 1.7:1.0. The results showed that negatively charged chlorophyll (sodium copper chlorophyllin) and positively charged dye (methyl violet) were efficiently extracted into the upper phase. The negatively charged methyl orange (pH>7) was moved into the upper phase mostly while amphoteric methyl orange (pH<3) was distributed in the two phases uniformly. Except for hydrophobic force, charge interaction between solute and surfactant also play an important role in the extraction process. 相似文献
109.
研究了Co(Ⅱ)、Ni(Ⅱ)-NH3-XO混配络合物和Co(Ⅱ)、Ni(Ⅱ)-NH3-XO-CTMAB多元络合物的形成条件及吸收光谱特性,结果表明,在pH 9.5的氨性缓冲溶液中,[NH3]/[XO]值在100~400范围内所形成的钴、镍多元络合物的最大吸收波长分别为530和590 nm,钴的多元络合物在0~2.0 mg.L-1、镍的多元络合物在0~2.6 mg.L-1范围内符合比耳定律,相对标准偏差分别为2.1%和1.9%。 相似文献
110.
研究了水溶液中双环[2,2,1]-2,5庚二烯-2,3-二羧酸在吖和吖啶橙的敏化作用下的光诱导价键异构化反应。量子效率分别为0,33(AY)和0,31(AO)。 相似文献