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81.
M. E. Chacón Villalba A. Navaza N. Dupont J. Marrot E. L. Varetti P. J. Aymonino 《Journal of chemical crystallography》2007,37(8):573-577
The crystal structure of [Co(NH3)5NO3](NO3)(PF6) ·1.5 H2O was studied by X-ray diffraction methods in order to obtain the unknown molecular structure of the [Co(NH3)5NO3]2+ cation . The substance crystallizes in the monoclinic system, space group C2/m, with a = 18.6231(6) ?, b = 7.8757(3) ?, c = 9.6434(3) ? and β = 95.484(2)°. An infrared and Raman study of the bromide salt was also performed and the spectra interpreted
with the aid of 14NO3/15NO3 isotopic replacement and quantum chemistry calculations.
E.L. Varetti — Member of the Carrera del Investigador Científico, CONICET, R. Argentina 相似文献
82.
83.
Selective removal of nitrate by using a novel macroporous acrylic anion exchange resin 总被引:1,自引:0,他引:1
Sandra Mueller 《中国化学快报》2012,23(5):603-606
An anion exchange resin NDP-5 has been prepared successfully and applied on the selective removal of nitrate from SO42-/ NO3- binary co-existence system.The composition and morphology of NDP-5 were confirmed by FT-IR and SEM.The NDP-5 resin exhibits the completely different behavior on the adsorption capacity,adsorption kinetic and the effect of the completing anion in the absence or presence of sulfate,compared to D213.And,the resultants of kinetic are well fitted by the pseudo-first-order and pseudo-second-order models.These results are very important to develop novel resins with great features. 相似文献
84.
Through three stories about nitrates, a storytelling technique is used to describe the main uses of nitrates today, including agricultural fertilizers, industrial explosives, and food preservatives. Nowadays, nitrate is suspected to be the main cause of carcinogenesis, but one coin has two sides; in fact, nitrates play an important role both in the ecological environment and in the human body. Therefore, the public can understand more about the applications of nitrates from this article. Through the accidental discovery of a rural couple in a wartime setting, this article describes the uses of nitrate in agriculture, antiseptic, immune systems and blood circulation system. 相似文献
85.
《Ultrasonics sonochemistry》2014,21(1):69-75
A sonophotochemical oxidation process has been used for the treatment of an aqueous solution of phenol. The aim of this work is to evaluate the effect of nitrate ions on hydroxyl radical production and on phenol oxidation. It has been demonstrated that ultrasound can produce NOx (nitrate and nitrite), with a production rate of 2.2 μM min−1. The photolysis of nitrate can significantly improve the hydroxyl radical production. The apparent rate constant for hydroxyl radical production increased from 0.0015 min−1 to 0.0073 min−1 while increasing initial nitrate concentration from 0 to 0.5 mM. The concentration of hydroxyl radical was directly proportional to the initial nitrate concentration. Using US/UV process, the apparent reaction rate constant of phenol degradation in the presence of nitrate reached 0.020 min−1, which was relatively lower than the value obtained (0.027 min−1) in the absence of nitrate. It appeared that, nitrate ions can inhibit the sonochemical degradation of organic compounds such as phenol. 相似文献
86.
Solid Contact Nitrate Ion‐Selective Electrode Based on Ionic Liquid with Stable and Reproducible Potential 下载免费PDF全文
Cecylia Wardak 《Electroanalysis》2014,26(4):864-872
A simple, fast and cheap method of preparation of solid contact nitrate ion‐selective electrode is proposed. The electrode membrane phase consist of only three components: PVC, plasticizer and ionic liquid (IL).The ionic liquid trihexyltetradecylphosphonium chloride is used in triple function as ionophore, as lipophilic ionic component in order to reduce membrane resistance, and as transducer media in order to stabilize the potential of internal Ag/AgCl electrode. The electrical properties of the membrane were studied by electrochemical impedance spectroscopy and the influence of the interfacial water film was evaluated by potentiometric water layer test. 相似文献
87.
《Comptes Rendus Chimie》2014,17(7-8):790-800
Activity and selectivity of bimetallic catalysts for two model reactions, citral hydrogenation in isopropanol and nitrate reduction in water, are reviewed on the basis of results obtained over bimetallic systems prepared in our laboratory, notably by redox techniques. The parent metal is generally a noble metal (Rh, Pd, Pt), while the additive is most often a non-noble metal (Ge, Sn, Cu…) whose oxidation state plays an important role in hydrogenation. Dramatic improvements of the selectivity to unsaturated alcohols are observed in citral hydrogenation with adequate deposition of the additive and pretreatment of the final catalyst. In nitrate reduction, the second metal essentially affects the first step of the process (conversion of nitrate to nitrite) but the global selectivity (limitation of NH3 formation) may be significantly improved by tuning the couple parent metal–additive. Other aspects such as the choice of the support and the optimization of reaction conditions (temperature, pressure, pH effects in water) are also discussed. 相似文献
88.
基于NO_2~-、NO_3~-和Fe(Ⅲ)对甲基橙光化学褪色反应的催化作用,利用自制流通式光化学反应器,建立了流动注射光化学反应同时测定NO_2~-和NO_3~-以及测定Fe(Ⅲ)的新方法。测定NO_2~-和NO_3~-的线性范围都是0.1~3.2mg/L,每小时可测30~40个样品,测定Fe(Ⅲ)的线性范围为0.06~1.2mg/L,进样频率为60~80次/h。应用于蔬菜中NO_2~-、NO_3~-的测定和茶叶中铁的测定,结果满意。 相似文献
89.
90.
Tirumalesh K 《Talanta》2008,74(5):1428-1434
This study describes a new ion chromatography method using a low-capacity anion exchange column with amperometric and absorbance detection for rapid and simultaneous determination of Br− and NO3− in contaminated waters where one of these ions is present in excess compared to other. The use of two detectors overcomes the problem of baseline separation for Br− and NO3− for accurate quantification, which was commonly encountered when using a low-capacity anion exchange column and suppressed conductivity detection mode. The method achieved accurate quantification of these two ions without requirement of baseline separation. The accuracy of 2.8% for NO3− was determined using a quality control sample obtained from UN GEMS/Water PE Study No. 6. The detection limits for Br− and NO3− were 20 and 6 μg l−1 (25 μl sample), respectively. Linearity of these two ions was over three orders of magnitude with a correlation coefficient >0.998. The influence of potential interfering ions was also studied followed by the determination of Br− and NO3− in seawater, unsaturated zone water, soil extract and groundwater. 相似文献