In general,a microemuision consists of oil,water,surfactant(s)and possibly cosurfactant(s).In this paper,a novel surfactant-free microemulsion(SFME)is reported,which is composed of furaldehyde(oil phase),water and eth...
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In general,a microemuision consists of oil,water,surfactant(s)and possibly cosurfactant(s).In this paper,a novel surfactant-free microemulsion(SFME)is reported,which is composed of furaldehyde(oil phase),water and ethanol without a traditional surfactant of the amphiphilic molecular *** phase behavior of this ternary system was studied finding that there is a single-phase microemulsion region and a two-phase region in the ternary *** electrical conductivity measurement was undertaken to investigate the microregion of the single-phase microemulsion *** the basis of the percolation theory,the single-phase microemulsion region was subdi-vided into three different microregions:furaldehyde-in-water(O/W),bicontinuous region and water-in-furaldehyde(W/O),which were confirmed by freeze-fracture transmission electron microscopy(FF-TEM)*** sizes of the microemulsion droplets are in the range of 30-80 *** surfactant-free emulsions(SFE)reported are O/W type and turbid,the significant apparent characteristic of SFME reported here is transparent,different from the *** stability change of the SFME was not evidently observed after storage at room temperature for 22 months up to now.
Polymerization reactions in vesicles are known to fix the vesicular structure to provide stabilized hollow colloidal nanoparticles used as biological membrane models, drug delivery vehicles, or templates for the synth...
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Polymerization reactions in vesicles are known to fix the vesicular structure to provide stabilized hollow colloidal nanoparticles used as biological membrane models, drug delivery vehicles, or templates for the synthesis of nanostructures. As a precursive work of polymerization directly from vesicles, a polymerizable surfactant, allyl dodecyl dimethylammonium bromide (ADDB) was synthesized, and spontaneous stable vesicles were formed from aqueous solutions of ADDB and sodium dodecyl sulfonate (SDS) in equimolar composition. The aqueous mixture of ADDB/SDS could form homogeneous solutions even at a high surfactant or sodium bromide (NaBr) concentration. Before polymerization, salt effect on the polymerizable vesicles was investigated by using dynamic light scattering (DLS) and freeze-fracture transmission electron microscopy (FF-TEM) measurements. It was interestingly revealed by the DLS method that the vesicle size increased from 83 nm in a salt-free solution to 250 nm with increasing the salt concentration to 250 mmol/L, but decreased from 250 to 180 nm with increasing the salt concentration to 1000 mmol/L. The same meaningful trend was disclosed by the FF-TEM measurements that when NaBr concentration was below 150 mmol/L the dispersed individual vesicle size was about 70 nm but it decreased to 20 nm while the NaBr concentration was above 400 mmol/L. The causation of increment of average aggregate radius can be attributed to the fusion and flocculation of vesicles observed clearly under a TEM imagine. The decrease of vesicle size results from the fact that, at a high salt concentration, electrolyte screens the interaction between the charged head groups, thus entropic increase drives big vesicles to decrease to small ones.
Generally, a microemulsion consists of oil, water, surfactant and sometimes cosurfactant. Herein, for the first time to our knowledge, a novel surfactant-free microemulsion (SFME), consisting of furaldehyde (oil phase...
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Generally, a microemulsion consists of oil, water, surfactant and sometimes cosurfactant. Herein, for the first time to our knowledge, a novel surfactant-free microemulsion (SFME), consisting of furaldehyde (oil phase), water and N,N-dimethyl formamide (DMF) without the amphiphilic molecular structure of traditional surfactant is re-ported. The phase behavior of the ternary system was investigated, finding that a single-phase microemulsion region and a two-phase region were formed. The electrical conductivity measurement was employed to investigate the sin-gle-phase microemulsion region. On the basis of the percolation theory, the single-phase microemulsion region was identified to consist of three different microregions: furaldehyde-in-water (O/W), bicontinuous region and water-in-furaldehyde (W/O), which were further proved by freeze-fracture transmission electron microscopy (FF-TEM) observations. The diameter of the microemulsion spherical droplets is in the range of 40-70 nm.
Onion-like fullerenes (OLFs) were synthesized by arc discharge in benzene using graphite as electrode and ferrocene as catalyst. The effect of ferrocene on the morphologies and structures of the OLFs was investigated ...
Onion-like fullerenes (OLFs) were synthesized by arc discharge in benzene using graphite as electrode and ferrocene as catalyst. The effect of ferrocene on the morphologies and structures of the OLFs was investigated by HRTEM and XRD. Results show that ferrocene directly influenced the morphology and yield of OLFs: The degree of graphitization is better. The diameters of the OLFs can be controlled in the range between 10 and 30 nm The method described here suggests a novel and promising route to synthesize OLFs in large scales.
The ternary hybrid films consisting of chitosan (CS), polyethylene glycol (PEG) and nano-sized silica which was surface-modified by amino groups (RNSA) were prepared. The structures of the blend membranes were charact...
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A pure blue light emitting material bis-2-(2-hydroxyphenyl) benzimidazole zinc has been synthesized. Its structure, energy band, photoluminescent property, film-forming ability, and thermal properties were charaterize...
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A pure blue light emitting material bis-2-(2-hydroxyphenyl) benzimidazole zinc has been synthesized. Its structure, energy band, photoluminescent property, film-forming ability, and thermal properties were charaterized by elemental analysis,1H-NMR, IR, UV-vis absorption, cyclic voltammetry, photoluminescent spectra, atomic force microscopy, and TG-DTG technique. The results show that the complex had a good thermal stability. UV-vis absorption bands of Zn (pbm)2were located at about 299, 334, 357. Its optical gap, HOMO energy and LUMO energy were 3.03, -5.72 and -2.69 eV, respectively. Zn (pbm)2formed dense film by vacuum vapor deposition. The maximum emitting wavelength of Zn (pbm)2was 445 nm, with FWHM being 81 nm and color purity being 0.8599, which indicates that this complex is an excellent blue-emitting material. The complexe was expected to find applications in organic electroluminescence diodes through appropriate device design.
Onion-like Fullerenes (OLFs) were synthsized by arc discharge in benzene and ferrocene using graphite as electrode. The effect of ferrocene on synthesis of OLFs was discussed. High resolution transmission electron mic...
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Onion-like Fullerenes (OLFs) were synthsized by arc discharge in benzene and ferrocene using graphite as electrode. The effect of ferrocene on synthesis of OLFs was discussed. High resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) technique were used to characterize morphology and structure of the products. The results show that the yield of OLFs might be improved if ferrocene is used as catalyst. The degree of graphitization is higher. The diameters of OLFs are in the range from 10 to 30 nm.
Most experimental and decoding algorithm studies of brain neural signals assume that neurons transmit information as a rate coding, but recent studies on the fast cortical computations indicate that temporal coding is...
Most experimental and decoding algorithm studies of brain neural signals assume that neurons transmit information as a rate coding, but recent studies on the fast cortical computations indicate that temporal coding is probably a more biologically plausible scheme used by neurons. We introduce spiking neural networks (SNN) which consist of spiking neurons propagate information by the timing of spikes to analyze the cortical neural spike trains directly without temporal information lost. The SNN based temporal pattern classification is compared with the conventional artificial neural networks (ANN) based firing rate analysis. The results show that the SNN algorithm can achieve higher accuracy, which demonstrates that temporal coding is a viable code for fast neural information processing and the SNN approach is suitable for recognizing the temporal pattern in the cortical neural signals.
Rare-earth oxide graphite intercalation compounds (CeO-GICs) were prepared using graphite and CeOas raw materials by vacuum heat-treatment. The stage-5 GICs was formed after heat treatment at 800 ℃, and it was examin...
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Rare-earth oxide graphite intercalation compounds (CeO-GICs) were prepared using graphite and CeOas raw materials by vacuum heat-treatment. The stage-5 GICs was formed after heat treatment at 800 ℃, and it was examined and characterized by X-ray diffraction (XRD). The XRD analysis of intercalation compounds indicated that a number of non-carbon reactant (atom, molecule, ion or groups) could intercalate the layers of graphite with reticulated layer structure physically. Consequently the layered structure of graphite changed and new physical and chemical properties were obtained. X-ray photoelectron spectroscopy (XPS) suggested that the compound intercalated into graphite should contain CeⅣ compounds.
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