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181.
Lie symmetries and solitons in nonlinear systems with spatially inhomogeneous nonlinearities 总被引:1,自引:0,他引:1
Belmonte-Beitia J Pérez-García VM Vekslerchik V Torres PJ 《Physical review letters》2007,98(6):064102
Using Lie group theory and canonical transformations, we construct explicit solutions of nonlinear Schr?dinger equations with spatially inhomogeneous nonlinearities. We present the general theory, use it to show that localized nonlinearities can support bound states with an arbitrary number solitons, and discuss other applications of interest to the field of nonlinear matter waves. 相似文献
182.
This paper deals with the photo-induced fluorimetric determination of the herbicide Fluometuron with the aid of a continuous-flow
assembly of the emergent and new methodology known as Multicommutation which was provided with an on-line photoreactor. Maximum
fluorescence intensity was observed at basic pH solutions, 1×10−4 mol l−1 NaOH, after 1.4 min of irradiation and being the maximum at λexc 247.0 nm and λem 325.0 nm.
The influence of different experimental parameters either chemical (pH, surfactants presence, solvent polarity and temperature)
or hydrodynamic (time of photo-degradation, size and number of different segments and flow-rate) was tested.
The linear dynamic range was from 0.01 to 4.0 mg l−1 of Fluometuron; the inter-day reproducibility (as R.S.D.) of the slope was 0.001% and 1.7% from the peaks intra-day reproducibility.
A large series of potential interferents was studied and finally the method was applied to human urine, soil, formulation
and water samples. 相似文献
183.
Schubert M Balcazar M Lopez A Peña P Flores JH Knöller K 《Isotopes in environmental and health studies》2007,43(3):215-226
The non-aqueous phase-liquid (NAPL)-contaminated aquifer at a major refinery site in Mexico was investigated. Owing to the depth of the contaminated aquifer section (NAPL source zone) of over 100 m below the surface, the actual aquifer material was not accessible for sampling. Information on the residual NAPL contamination of the aquifer could only be obtained indirectly by analysing groundwater samples from a few wells available at the site. To tackle the problem, an approach alternative to conventional groundwater analysis for dissolved NAPL was chosen. For evaluating the recent contamination and estimating its probable future development, the radioisotope radon-222 and the stable isotopes 13C, 34S and 18O were used as naturally occurring contamination tracers and process indicators. Radon was used as partitioning tracer for the approximate localization and semi-quantitative assessment of the NAPL source zone. The stable isotopes were used as indicators for naturally occurring biodegradation processes, which might potentially be implemented into future remediation schemes. 相似文献
184.
HOU Xiao-Mina b CHEN Ming-Huanga② XIE Jie-Mingc YE Xiao-Minga ZHAO Geng-Xianga b YANG Fenga b CHEN Li-Qingd HUANG Ming-Donga a 《结构化学》2006,25(9):1035-1038
1 INTRODUCTION The ribosome-inactivating proteins (RIPs) are RNA N-glycosidases[1, 2] which inactivate ribosomes by cleaving a single N–C glycosidic bond between adenine and ribose at A4324 in the 28s rRNA of rat. Because of the removal of one adenine from rRNA, elongation factorⅡ(EF-2) can not bind to the 60S subunit, so RIPs can arrest protein synthesis. RIPs can be classified into three types based on the struc- tures of genes and mature proteins[3]. Type 1 RIPs with molec… 相似文献
185.
ZHAO Hui-Minga YUAN Li-Xiaa YANG Guo-Yinga SUN De-Shengb WANG Zun-Yaoa② CHI Qing-Qinga a 《结构化学》2006,25(10):1280-1286
1 INTRODUCTION Interhalogen compounds have played an impor- tant role in environment and chemical engineering production. During the course of ozone exhaustion induced by sunlight in polar region, Br2, BrCl and HOBr are all precursors of Br atom[1]. Lately, scien- tists have detected that the content of BrCl in polar region sunlight was 35 ppt, larger than that of Br2 (25 ppt). Previous studies suggested that the con- centration of BrCl and O3 exhibits obvious negative correlation: w… 相似文献
186.
Synthesis and Crystal Structural Characterization of a Thiosemicarbazone Derived from 4-Acylpyrazolone 总被引:1,自引:0,他引:1
LIU Guang-Feia LIU Langa HU Xina JIA Dian-Zenga② YU Kai-Beib a 《结构化学》2006,25(10):1233-1237
1 INTRODUCTION Pyrazol-5-one derivatives form an important class of organic compounds due to their structural che- mistry and biological activities as analgesic, antipy- retic, anti-inflammatory and hyperglycemic agents[1~4]. Even the simplest pyrazol-5-one derivatives like antipyrine and amidopyrine are widely used in anal- gesic medicine[5, 6]. On the other hand, thiosemicar- bazones, especially heterocyclic thiosemicarbazones, have been the subject of extensive investigations be- cause… 相似文献
187.
Antoine Salden Maik Budde Carolina Alejandra Garcia-Soto Omar Biondo Jairo Barauna Marzia Faedda Beatrice Musig Chloé Fromentin Minh Nguyen-Quang Harry Philpott Golshid Hasrack Domenico Aceto Yuxiang Cai Federico Azzolina Jury Annemie Bogaerts Patrick Da Costa Richard Engeln María Elena Gálvez Timo Gans Tomas Garcia Vasco Guerra Carlos Henriques Monika Motak Maria Victoria Navarro Vasile I.Parvulescu Gerard Van Rooij Bogdan Samojeden Ana Sobota Paolo Tosi Xin Tu Olivier Guaitella 《Journal of Energy Chemistry》2023,(11):318-342
This paper brings the comparison of performances of CO2 conversion by plasma and plasma-assisted catalysis based on the data collected from literature in this field, organised in an open access online database. This tool is open to all users to carry out their own analyses, but also to contributors who wish to add their data to the database in order to improve the relevance of the comparisons made, and ultimately to improve the efficiency of CO2 conversion by plasma-catalys... 相似文献
188.
MAO Shao-Yu a② KANG You-Juna MI Jin-Xiaoa② LI Man-Rongb WEI Zan-Bina WU Xue-Yanb ZHAO Jing-Taib a 《结构化学》2006,25(2):173-179
1 INTRODUCTION Considerable research effort on the heavy metal fluoride glasses like barium, zirconium fluoride and a series of rare-earth fluorozirconate compounds du- ring the last two decades was initiated by the broad optical transmission window of these glasses and thereby the potential for ultralow-loss optical fi- bers[1~10]. The fluorozirconate of alkali metals was first reported in 1938[11], and most of the sodium and potassium fluorozirconates were reported amongthe 1940s and 19… 相似文献
189.
GAO Dong-Zhaoa WANG Shu-Pinga CHEN Jina LI Li-Cuna b LIAO Dai-Zhenga JIANG Zong-Huia② YAN Shi-Pinga a 《结构化学》2006,25(2)
1 INTRODUCTION Nitronyl nitroxides, independently or in combina- tion with metal ions, have been one of the most wi- dely studied systems in molecular magnetism for understanding radical-radical or metal-radical inte- ractions as well as for synthesizing organic ferroma- gnets and metal-radical magnetic materials[1~4]. Up to now, lots of metal-radical complexes have been reported[5~8]. On the other hand, cooperative inter- molecular interactions, such as coordination bonds, hydrogen bon… 相似文献
190.
LI Jun-Linga① GU Juna QIU Guang-Minb a 《结构化学》2006,25(5):589-593
1 INTRODUCTION Since the introduction of QSAR by Hansch and Fujita in 1964, Deutsch and Hansch have quickly used it in the study of nitrophenylamine sweet reagents. They found good correlation between their distribution coefficients in octanol/water system and sweetness degree. Subsequently, they detected that vibration of aroma-substituent compounds has so- mething to do with sweetness. Henceforth, statistic correlations between structure and sweetness ofseries compounds have been inv… 相似文献