Papers by Keyword: Rhodamine

Abstract: A method for the trace analysis of rhodamine with colorimetric measurements based on solid-phase extraction by transparent polymethacrylate matrix is described. The quantity of sorbed РММ reagent is proportional to intensity of its painting and it depends on conditions of modification: рН, concentration of the reagent in solution and durations of processing. The interactions between PMM and rhodamine were studied by solid-phase spectrophotometry under batch conditions. The kinetic profiles of sorption at different temperatures are similar. This suggests that the sorption mechanism is mainly due to the formation of an inclusion complex through host–guest interactions.

Abstract: The field tracer test is dropping quantitative tracer materials in the entrance of ponor upstream and to monitor online concentration of tracer materials in the main export of underground river downstream, and then deduce the type of groundwater pipe and the source of supply according to the concentration. This thesis takes the landslide areas in highways across form Quanzhou to Nanning and in tunnels connecting Ji’an with Zhongjiashan in Lianhua (a town in Pingxiang) as the research object, explores the supply source of tunnel water, meanwhile uses three tracer materials of different nature, namely the fluorescein sodium, fluorescent whitening agent and rhodamine, to place 4 drop points and 3 receiving points within 20 square meters of the surveyed area, to conduct groundwater tracer test. The test shows that there is no obvious connection between tunnel water gushing and F₅ fracture main ditch surface water as well as F₅ tectonic fracture zone; Fault F₂ has good conductivity, and the gushing water in the right hole in the import and export of tunnel is related with F₂ fault tectonic fracture zone.

Abstract: The recognition and sensing of biologically and environmentally important species has emerged as a significant goal in the field of chemical sensors in recent years¹. Fluorogenic methods in conjunction with suitable probes are preferable approaches for the measurement of these analytes because fluorimetry is rapidly performed, is nondestructive, is highly sensitive, is suitable for high-throughput screening applications^2,3. We synthesized rhodamine derivatives compounds by a Schiff base reaction.

Abstract: Two novel fluorescent chemodosimeters will be presented for the selective detection of cysteine over homocysteine and glutathione in aqueous solvent. First, a rhodamine-based fluorescent probe (1) will be reported. Masked with a para-hydroxybenzyl alcohol (HBA) unit, probe 1 initially showed a weak fluorescence but displayed a strong fluorescence through a series of reactions of Michael addition and intramolecular cyclization of cysteine, followed by deprotection of HBA. The caged probe (1) exhibited a selective and sensitive response toward cysteine over homocysteine and glutathione in HEPES buffer. Secondly, a fluorescein-based fluorescent probe will be discussed. A bromoacetyl functionalized fluorescein chemodosimeter (2) was utilized as a fluorescent probe for cysteine. The probe showed a selective and sensitive response to cysteine over homocysteine and glutathione in aqueous buffer through a rapid cyclization reaction. When cysteine was added, a fast fluorescence turn-on change of 2 was observed and applied to the in-vivo imaging of cysteine.

Abstract: A method for the trace analysis of rhodamine and eosine with colorimetric measurements based on solid-phase extraction (SPE) by transparent polymethacrylate matrix (PMM) is described. Solid-phase extraction on PMM allowed a 380-fold enrichment of the dyes if 10 mL sample volume is used with extraction efficiencies 98%. The method enables the determination of rhodamine to 0.06 mg/L and eosine to 1.2 mg/L combined with a fast and easy sample-preparation (pH-adjusting prior to SPE). Simultaneous extraction and determination of rhodamine and eosine in reservoir samples with high salinity confirmed the applicability and reproducibility of the method. Batch adsorption results indicated that Langmuir isotherm described the adsorption isotherms better.

Abstract: Copper hydroxyphosphate,as self-assembled nanoparticles, was synthesized by using a hydrothermal method,with cupric acetate (Cu(CH3COO)2·H2O) and diammonium hydrogen phosphate ((NH4)2HPO4) as raw materials. Physical property of copper hydrophosphate was characterized by X-ray diffraction (XRD), Field-emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), and Ultraviolet obvious diffuse reflection(UV-vis DRS). No surfactants or templates were added in the procedure of preparation. By simply adjusting the pH from 3 to 9, the morphology of copper hydrophosphate varied from microrods to walnutshaped microspheres. Photocatalytic activity of the samples was also investigated. Photo decoloration of Rhodamine B in water under visible light irradiation shows that copper hydrophosphate (pH=7) have the best photocatalytic activity: Photodecoloration activity of 100 mL Rhodamine B (10 mg/L) was 98 % under illumination for 30 min.

Abstract: We report the effect of solvent on the rhodamine 6G encapsuled into channels of mesoporous silica, synthesized by two-step process that gives intermediary stable hybrid micelles. Mesoporous materials have been obtained by the method that involves surfactant micelles (mainly cationic) and inorganic precursor of the structure to be obtained. MSU-X type mesoporous silica has been synthesized with polyethylene oxide surfactant as the directing-structure agent and tetraethyl orthosilicate Si(OEt)4 as the silica source. The influence of the solvent on the encapsulation of rhodamine dye was systematically explored, specially its influence on the luminescence properties. Rhodamine 6G encapsuled into mesoporous silica channel was characterized by UV-Vis and luminescence spectroscopies, scanning electron microscopy, small angle x ray scattering and N2 sorption-desorption. The pore size and the solvent effects into luminescence dye encapsuled into mesoporous silica channels are observed in the visible absorption and emission spectra of rhodamine 6G. The intense photoluminescence band of rhodamine 6G dye is in 500 to 600 nm region. The observed shift of the absorption and emission bands can be assigned to the effect of the solvents dielectric constant and pore size of mesoporous silica.