Methanol Suspension Research Articles

Electrophoretic deposition of titania nanostructured coatings for photodegradation of methylene blue

The suspensions of titania nanoparticles were prepared in different alcohols (methanol, ethanol, isopropanol and butanol) using polyethyleneimine (PEI) as dispersant. The results of sedimentation, conductivity, zeta potential, FTIR and thermal analysis showed that PEI macromolecules are protonated in the suspensions and then adsorbed on the particles enhancing their positive surface charge and so colloidal stability. Optimum concentration of PEI (PEI*) was lower in large molecular size alcohols due to its higher adsorption efficiency. PEI* was 0.75, 0.5, 0.5 and 0.25 g/l in methanolic, ethanolic, isopropanolic and butanolic suspensions, respectively. Electrophoretic deposition (EPD) was performed at 60 V in different alcoholic suspensions. EPD rate was the fastest in the suspensions with PEI* due to the highest mobility of particles. In contrast to the coatings deposited for 1 min from isopropanolic and butanolic suspensions, those deposited at same conditions from methanolic and ethanolic ones severely cracked during drying owing to their higher thickness and lower PEI contents (acting as the binder). The coatings deposited from methanolic and ethanolic suspensions with PEI* had finer and rougher microstructures. The sintered coating deposited at 60 V for 10 s from ethanolic suspension with PEI* had crack-free microstructure with the thickness of ≈ 130 μm. This coating degraded ≈ 24% of methylene blue from its aqueous solution (30 ml with the concentration of 5 mg/l) within 2 h under UV illumination. Photodegradation of MB on the surface of titania coating obeyed the first order kinetics law.

Effect of morphology on the electrophoretic deposition of hydroxyapatite nanoparticles

Electrophoretic deposition (EPD) was performed from alcoholic suspensions of spherical (SHA) and fiber (FHA) hydroxyapatite nanoparticles. FHA particles were horizontally aligned in deposits prepared at lower voltages since they can find enough space and time to rotate upon reaching the deposit and sit horizontally on it. While, they are more randomly oriented at higher voltages since more FHA particles aligned parallel to electric field reach to the substrate and also particles cannot find enough time and space for rotation. FHA particles are highly interlocked together in FHA deposits reinforcing them and also the drying shrinkages are lower for them resulting in their less cracking. The cracks are parallel to each other in FHA coating deposited from methanolic suspension at 5 V due to the more horizontal and parallel alignment of FHA particles in it. The crack-free SHA coating decreased the corrosion rate of substrate more efficiently due to its less porosity.

Direct Electrical Detection of Iodine Gas by a Novel Metal-Organic-Framework-Based Sensor.

High-fidelity detection of iodine species is of utmost importance to the safety of the population in cases of nuclear accidents or advanced nuclear fuel reprocessing. Herein, we describe the success at using impedance spectroscopy to directly detect the real-time adsorption of I2 by a metal-organic framework zeolitic imidazolate framework (ZIF)-8-based sensor. Methanolic suspensions of ZIF-8 were dropcast onto platinum interdigitated electrodes, dried, and exposed to gaseous I2 at 25, 40, or 70 °C. Using an unoptimized sensor geometry, I2 was readily detected at 25 °C in air within 720 s of exposure. The specific response is attributed to the chemical selectivity of the ZIF-8 toward I2. Furthermore, equivalent circuit modeling of the impedance data indicates a >105× decrease in ZIF-8 resistance when 116 wt % I2 is adsorbed by ZIF-8 at 70 °C in air. This irreversible decrease in resistance is accompanied by an irreversible loss in the long-range crystallinity, as evidenced by X-ray diffraction and infrared spectroscopy. Air, argon, methanol, and water were found to produce minimal changes in ZIF-8 impedance. This report demonstrates how selective I2 adsorption by ZIF-8 can be leveraged to create a highly selective sensor using >105× changes in impedance response to enable the direct electrical detection of environmentally relevant gaseous toxins.

Photocatalytic hydrogenation of furan to tetrahydrofuran in alcoholic suspensions of metal-loaded titanium(iv) oxide without addition of hydrogen gas.

The use of metal co-catalysts broadens the application of photocatalytic reduction without the use of dihydrogen (H2) gas. We examined photocatalytic hydrogenation of furan, a representative heterocyclic compound and a compound derived from biomass, in alcoholic suspensions of metal-loaded titanium(iv) oxide (TiO2) under a H2-free condition and we found that furan was almost quantitatively hydrogenated to tetrahydrofuran with a high apparent quantum efficiency of 37% at 360 nm when palladium was used as a co-catalyst. Effects of different metal co-catalysts, different amounts of the co-catalyst, the type of TiO2, the type of alcohol, light wavelength and reusability for furan hydrogenation were investigated. Based on the results, the functions of TiO2 and the co-catalyst and the reaction process are discussed.

Electrophoretic deposition of ZnO-CeO2mixed oxide nanoparticles

ZnO–CeO2 nanoparticles were synthesized by microwave combustion and deposited by electrophoretic deposition (EPD). The effect of using two different alcohols, ethanol and methanol, was investigated on EPD behavior and morphology of deposited film. Moreover, the effect of concentration of nanoparticles and applied voltage on the mass of deposit and the variation in the current density were investigated. With a change in the alcohol type, the surface morphology of deposition changed and some voids were observed on the deposition surface in ethanol. In all cases, with increasing concentration of nanoparticles in suspension, the number of developed cracks increased. Besides, a rise in voltage led to an increase in the number of cracks. The EPD processes in ethanol and methanol suspension were simulated over time using different zero boundary conditions. Hemi-spherical morphology was seen for the nanoparticles deposited in ethanol. This kind of growth was simulated based on the changes in electrical field.

Divergent topologies in divalent metal furandicarboxylate or thiophenedicarboxylate coordination polymers with bis(4-pyridylformyl)piperazine coligands

Hydrothermal reaction of a metal nitrate, 2,5-furandicarboxylic acid (H2fdc), and the long-spanning dipyridylamide ligand bis(4-pyridylformyl)piperazine (bpfp) produced three coordination polymers which were structurally characterized by single-crystal X-ray diffraction. {[Cd2(fdc)2(bpfp)(H2O)4]·10H2O}n (1) possesses 1D 3-connected coordination polymer ladders co-crystallized with decameric water molecule clusters. {[Cu(fdc)(bpfp)(H2O)2]·2H2O}n (2) exhibits (4,4) grid coordination polymer layers stacked in an unusual parallel ABCD pattern. {[Ni(fdc)(bpfp)(H2O)2]·4H2O}n (3) also manifests (4,4) grid coordination polymer layers, but these engage in 2D+2D→3D mutually inclined interpenetration. Hydrothermal reaction of metal nitrates, 2,5-thiophenedicarboxylic acid (H2tdc), bpfp afforded {[Zn(tdc)(bpfp)(H2O)]·2H2O}n (4), {[Cd(tdc)(bpfp)(H2O)]·2H2O}n (5), {[Ni2(tdc)2(bpfp)2(H2O)4]·3H2O}n (6), and {[Cu(tdc)(bpfp)(H2O)2]·3H2O}n (7). Compounds 4 and 5 exhibit (4,4) sawtooth coordination polymer layer motifs that engage in relatively uncommon 2D+2D→3D parallel interpenetration. Compounds 6 and 7 both showed 2D+2D→3D mutually inclined interpenetration of parallel sets of (4,4) grid layer motifs, but with different orientations of the heterocycles within their respective metal/tdc chain submotifs. Thermal properties of all new materials were also investigated. The luminescent cadmium and zinc derivatives 1, 4, and 5 were assayed as potential detectors for nitrobenzene in methanol suspension.

A 3D Cd(II)-organic coordination polymer demonstrating selective sensing of Zn2+ ion and nitrobenzene

Cd(II)-organic coordination polymer with the formula [Cd3(btdc)3(DMF)2(EtOH)2]·2EtOH·2H2O were solvothermally synthesized by treating Cd(II) nitrates with 2,2′-bithiophene-5,5′-dicarboxylic acid (H2btdc) and characterized by single crystal X-ray diffraction, elemental analysis, thermogravimetric analyses, IR spectroscopy and X-ray powder diffraction. Single-crystal X-ray diffraction studies indicate that the Cd(II) complex exhibits a 3D supramolecular framework, in which trinuclear Cd(II) clusters are connected by btdc ligands to form a 2D (4, 4) layer. Furthermore, the 2D (4, 4) layers stacked via AA mode. This complex displays strong fluorescent emission both in the solid state and in methanol suspension at room temperature, which can act as the fluorescent probe for selectively detecting Zn2+ ions and nitrobenzene through luminescence enhancing and quenching, respectively.

A thiadiazole-functionalized Zr(iv)-based metal–organic framework as a highly fluorescent probe for the selective detection of picric acid

A new, strongly luminescent Zr(IV)-based metal–organic framework (MOF) material (1) having a UiO-68 (UiO = University of Oslo) framework topology and incorporating the π-conjugated, thiadiazole-functionalized H2BTDB {H2BTDB = 4,4′-(benzo[c][1,2,5]thiadiazole-4,7-diyl)dibenzoic acid} ligand was synthesized under solvothermal conditions (150 °C, 24 h) using ZrCl4 and the H2BTDB ligand in DMF (DMF = N,N-dimethylformamide). The phase-purity of as-synthesized 1 was ascertained by X-ray powder diffraction (XRPD) analysis, Fourier transform infrared (FT-IR) spectroscopy and elemental analysis. Based on the thermogravimetric analyses, 1 is thermally stable up to 400 °C. XRPD experiments verify that activated 1′ retains its crystallinity when exposed to water, acetic acid and 1 M HCl solutions. As revealed by the steady-state fluorescence titration experiments, the thermally activated form of the compound (1′) showed a selective sensing behaviour towards 2,4,6-trinitrophenol (TNP, commonly known as picric acid), even in the presence of other potentially competing nitroaromatic explosive compounds. The estimated detection limit of 1′ for sensing TNP in methanol suspension was found to be 1.63 × 10−6 M. The highest fluorescence quenching ability of TNP can be attributed to both energy and electron transfer processes as well as electrostatic interactions between the hydroxyl group of TNP and the Lewis basic N-donor sites of the BTDB ligand. Endowed with its excellent detection efficiency, 1′ is a promising luminescent sensor material for the long-term, practical sensing of TNP.

Controllable assembly of zeolite beta monolayers and bilayers on various substrates using the Langmuir–Blodgett technique

The Langmuir–Blodgett (L–B) technique was employed to fabricate the monolayers and bilayers of nano-sized beta (nano-beta) crystals, and the monolayers of micrometer-sized beta (micro-beta) crystals on various substrates including glass plate, α-Al2O3 disk, glass capillary tube, copper wire, stainless-steel tube and γ-Al2O3 tube. With respect to the methanol suspension of 1 wt.% nano-beta modified with cetyltrimethylammonium bromide (CTAB), a two-region surface pressure-area isotherm was obtained, leading to the formation of both nano-beta monolayers and bilayers with satisfactory degree of coverage (DOC) and close packing (DCP) under each transfer surface pressure. When nano-beta crystals were dealuminated, the surface pressure-area relation was reduced to the one-region isotherm, and the resulting L–B film contained aggregated areas. As for the assembly of micro-beta crystals, both methanol and sec-butanol were used as the dispersant. The resulting micro-beta monolayer was randomly oriented with the sedimentation of large truncated-square-bipyramid crystals on compression by using the methanol suspension. The use of sec-butanol as the dispersant resulted in the enhanced hydrophobicity of micro-beta crystals due to the chemical reaction of sec-butanol molecules with surface silanols, leading to the formation of c-oriented micro-beta monolayers over various substrates, and simultaneously the sedimentation of large truncated-square-bipyramid crystals did not occur. Under the structure direction of the c-oriented micro-beta monolayer in the seeded growth, the dense and preferentially c-oriented zeolite beta film could be fabricated, which could not be formed on either the nano-beta monolayer or the micro-beta monolayer with random orientation. Therefore, it would be concluded that the growth of beta crystals over the seed layer could be followed by the epitaxial growth mechanism.

A mixed-crystal lanthanide zeolite-like metal-organic framework as a fluorescent indicator for lysophosphatidic acid, a cancer biomarker.

Two lanthanide zeolite-like metal-organic frameworks (Ln-ZMOFs) with rho topology, Tb-ZMOF and Eu-ZMOF, were constructed by self-assembly of a 4-connected lanthanide molecular building block and a bipyridine-dicarboxylate ligand. Varying the Tb(3+) and Eu(3+) ratio during synthesis afforded three mixed-crystal isostructural MZMOFs with variable Eu:Tb stoichiometry. Fluorescence studies revealed that a methanol suspension of one of these mixed crystals, MZMOF-3, exhibits selective detection of lysophosphatidic acid (LPA), a biomarker for ovarian cancer and other gynecologic cancers. Linear correlation between the integrated fluorescence intensity and the concentration of LPA was observed, enabling quantitative analysis of LPA in physiologically relevant ranges (1.4-43.3 μM). MZMOF-3 therefore has the potential to act as a self-referencing and self-calibrating fluorescent indicator for LPA.

Kinetic study of the radical scavenging of capsaicin in homogeneous solutions and aqueous Triton X-100 micellar suspensions.

A kinetic study of capsaicin (CAP) toward radicals has been performed using stopped-flow spectrophotometry in detail. The second-order rate constants (k2) for the reaction of CAP toward 2,2-diphenyl-1-picrylhydrazyl (DPPH) and galvinoxyl have been measured in methanol, ethanol, 2-propanol/water (5:1, v/v), and aqueous micellar suspensions containing 5% Triton X-100 (pH 4.0 to 10.0), respectively. The decay rates of DPPH and galvinoxyl for the reaction with CAP increased linearly in a concentration-dependent manner in homogeneous solutions and aqueous micellar suspensions. However, the k2 for CAP obtained in an aqueous micellar suspension showed notable pH dependence; that is, the reactivity of CAP increased with an increasing pH value from 4 to 10. In addition, a good correlation between the k2 value and the molar fraction of CAP (phenolate anion (CAP-O(-))/undeprotonated form (CAP-OH)) was observed. These properties are associated with the pKa of CAP. Furthermore, it was found that the CAP-O(-) reacts with galvinoxyl about 6 times as fast as the CAP-OH. These results indicate that sequential proton loss electron transfer from the phenolic hydrogen of CAP may be responsible for the scavenging of radicals in an aqueous micellar suspensions.

Fluorescent imino and secondary amino chitosans as potential sensing biomaterials

A variety of fluorescent imino and secondary amino chitosans were synthesized under very mild conditions by reaction of the biopolymer amino functions with aromatic aldehydes in an acidified methanolic suspension. Simultaneous reactions of several aldehydes with chitosan were successfully carried out, and kinetic studies showed that 1-pyrenecarboxaldehyde reacts the fastest among them. An unprecedented study on the evaluation of the degree of N-substitution (DS, ranging from 31.7% to 12.0%) for the chitosan Schiff bases by using solid state CPMAS 13C NMR is performed. A linear correlation between the DS obtained for the secondary amino chitosans by 1H NMR (55.3–10.2%) and those obtained by CPMAS 13C NMR (34.4–13.8%) has allowed us to calculate an empirical correlation factor that could be applied on chitosan-based aromatic systems. The new chiral-labelled chitosan derivatives exhibit a stable fluorescent behaviour, which was used to explore solvent sensoring applications.

Processing and Characterization of Nanoparticle Coatings for Quartz Crystal Microbalance Measurements.

The quartz-crystal microbalance is a sensitive and versatile tool for measuring adsorption of a variety of compounds (e.g. small molecules, polymers, biomolecules, nanoparticles and cells) to surfaces. While the technique has traditionally been used for measuring adsorption to flat surfaces and thin ridged films, it can also be extended to study adsorption to nanoparticle surfaces when the nanoparticles are fixed to the crystal surface. The sensitivity and accuracy of the measurement depend on the users’ ability to reproducibly prepare a thin uniform nanoparticle coating. This study evaluated four coating techniques, including spin coating, spray coating, drop casting, and electrophoretic deposition, for two unique particle chemistries [nanoscale zero valent iron (nZVI) and titanium dioxide (TiO2)] to produce uniform and reproducible nanoparticle coatings for real-time quartz-crystal microbalance measurements. Uniform TiO2 coatings were produced from a 50 mg/mL methanol suspension via spin coating. Nanoscale zero-valent iron was best applied by spray coating a low concentration 1.0 mg/mL suspended in methanol. The application of multiple coatings, rather than an increase in the suspension concentration, was the best method to increase the mass of nanoparticles on the crystal surface while maintaining coating uniformity. An upper mass threshold was determined to be approximately 96 µg/cm2; above this mass, coatings no longer maintained their uniform rigid characteristic, and a low signal to noise ratio resulted in loss of measurable signal from crystal resonances above the fundamental.

Synthesis, crystal structure and photoluminescent properties of a 3D Zn(II) coordination polymer

A new 3D coordination polymer [NH2(CH3)2]2[Zn7L4(DMF)2(H2O)3]·19H2O (1) (L=2,3′,5,5′-biphenyl tetracarboxylic acid) has been solvothermally synthesized and structurally characterized by IR, elemental analysis and single-crystal X-ray diffraction. Single-crystal X-ray diffraction studies indicate that 1 exhibits 3D framework with a one-dimensional (1D) channel. The luminescence properties have been studied, and the results showed that 1 displays strong fluorescent emissions both in the solid state and in methanol suspension at room temperature. More interesting, the addition of Fe3+ causes the fluorescence intensity of 1 to be weakened, which implies that it may be used as luminescent probes of Fe3+.

Preferential removal and immobilization of stable and radioactive cesium in contaminated fly ash with nanometallic Ca/CaO methanol suspension

In this work, the capability of nanometallic Ca/CaO methanol suspension in removing and/or immobilizing stable (133Cs) and radioactive cesium species (134Cs and 137Cs) in contaminated fly ash was investigated. After a first methanol and second water washing yielded only 45% of 133Cs removal. While, after a first methanol washing, the second solvent with nanometallic Ca/CaO methanol suspension yielded simultaneous enhanced removal and immobilization about 99% of 133Cs. SEM-EDS analysis revealed that the mass percent of detectable 133Cs on the fly ash surface recorded a 100% decrease. When real radioactive cesium contaminated fly ash (containing an initial 14,040Bqkg−1134Cs and 137Cs cumulated concentration) obtained from burning wastes from Fukushima were reduced to 3583Bqkg−1 after treatment with nanometallic Ca/CaO methanol suspension. Elution test conducted on the treated fly ash gave 100BqL−1 total 134Cs and 137Cs concentrations in eluted solution. Furthermore, both ash content and eluted solution concentrations of 134Cs and 137Cs were much lower than the Japanese Ministry of the Environment regulatory limit of 8000Bqkg−1 and 150BqL−1 respectively. The results of this study suggest that the nanometallic Ca/CaO methanol suspension is a highly potential amendment for the remediation of radioactive cesium-contaminated fly ash.

Engineering small MgAl-layered double hydroxide nanoparticles for enhanced gene delivery

In this paper we report an approach for engineering small MgAl-layered double hydroxide (sLDH) nanoparticles with the Z-average diameter of about 40nm. This method first requires co-precipitation of magnesium and aluminum nitrate solution with sodium hydroxide in methanol, followed by LDH slurry collection and re-suspension in methanol. The methanol suspension is then heated in an autoclave, followed by separation via centrifugation and thorough washing with deionized water. The nanoparticles are finally dispersed in deionized water into homogeneous aqueous suspension after 4–6day standing at room temperature. In general, sLDH nanoparticles have the Z-average size of 35–50nm, the number-average size of 14–30nm and the polydispersity index (PdI) of 0.19–0.25. The prepared sLDH suspension is stable for at least 1month when stored at fridge (2–8°C) or ambient (22–25°C) temperature. Moreover, sLDH nanoparticles are found to carry higher payloads of small double stranded DNA (dsDNA). More excitedly, sLDH nanoparticles transfect dsDNA into HEK 293T cells with a 5 to 6-fold greater efficiency compared to the larger LDH particles (Z-average diameter of 110nm).

Impact of alternate use of methanol on n-hexane biofiltration and microbial community structure diversity

The impact of introducing and suspending methanol on n-hexane biodegradation in trickle-bed-air-biofilters (TBABs) and the associated changes in microbial biodiversity is evaluated in this study. Four TBABs with n-hexane loading rate of 13.2g/m3h were evaluated. Two TBABs operated at pH 4 and the remaining at pH 7. The concentration ratios of methanol to n-hexane were 3:1 and 5:1, providing methanol loading rates of 37.7 and 64.5g/m3h, respectively. The removal efficiency (RE) of n-hexane in presence of methanol under pH 4 fluctuated between 81±5.7% and 88±11.6%. While for TBABs operating under pH 7, the RE varied between 34±12.7% and 69±11.2%. Methanol suspension triggered n-hexane REs of 93% and 82% for TBABs operating at pH 4 and pH 7, respectively. 16S and 18S rDNA sequencing analysis suggested that methanol inhibited n-hexane biodegrading microorganisms, while its suspension enhanced the microbial community diversity and promoted enrichment of the functional microorganisms degrading n-hexane.

Chloromethylated polystyrene cross-linked with divinylbenzene and grafted with vanadium(IV) and vanadium(V) complexes having ONO donor ligand for the catalytic activity

The ligand H2sal-iah (I), derived from salicylaldehyde and indole-3-acetic hydrazide, reacts with [VIVO(acac)2] in methanol to give oxidovanadium(IV) complex [VIVO(sal-iah)(H2O)] (1). In the presence of KOH, arial oxidation of 1 in methanol yields dioxidovanadium(V) complex K[VVO2(sal-iah)]·H2O (2). Complex 1 has been grafted via covalent bonding through imino nitrogen of the indole group to chloromethylated polystyrene cross-linked with 5% divinylbenzene {now abbreviated as PS-[VIVO(sal-iah)(H2O)] (3)}. Its oxidomethoxido vanadium(V) analog {PS-[VVO(OMe)(sal-iah)] (4)} can be obtained by aerial oxidation of methanolic suspension of 3. All these complexes are characterized by various spectroscopic techniques (IR, electronic, 1H and 51V NMR, electron paramagnetic resonance (EPR) and thermal as well as field-emission scanning electron micrographs (FE-SEM)) studies. The EPR spectrum of 3 indicates that the magnetically dilute VIVO-centers are well dispersed in the polymer matrix while EPR spectrum of 1 shows slightly different binding mode around vanadium center. 1H and 51V NMR spectra of 2 are compatible with the existence of expected dioxide species as the major product and oxidomethoxido species as a minor component in solution. Independent of the species presents in methanol, complexes 1 and 2 upon treatment with H2O2 both change to same oxidoperoxido species. The polymer-grafted complex 4 catalyzes the oxidation, by H2O2, of styrene and cyclohexene. Under optimized reaction conditions, the oxidation of styrene gave 95% conversion where styrene oxide, benzaldehyde, benzoic acid, 1-phenylethane-1,2-diol and phenylacetaldehyde are products. Oxidation of cyclohexene gave 96% conversion with cyclohexene oxide, 2-cyclohexene-1-ol, cyclohexane-1,2-diol and 2-cyclohexene-1-one as the major products. Neat complex K[VVO2(sal-iah)]·H2O (2) is equally active but the recyclability and heterogeneity tests of polymer-grafted complex make it better over neat analog.

Synthesis and field emission properties of carbon nanotube films modified with amorphous carbon nanoparticles by a simple electrodeposition method

Abstract Amorphous carbon nanoparticles (a-CNPs) on a multi-walled carbon nanotube (MWCNT) film, deposited on a silicon substrate, were synthesized using an electrodeposition combination from a methanol suspension of polydiallyldimethylammonium chloride-modified MWCNTs. A low-voltage electrophoretic deposition of the MWCNTs and a high-voltage electrochemical deposition of the a-CNPs were carried out to yield homogenously attached a-CNPs on the surfaces of the MWCNTs, and form a composite film with good adhesion to the substrate. This scalable technology can produce a large area of a-CNP/MWCNT film. And the field emission investigations show that the a-CNP/MWCNT film has turn-on electric field of 3.17 V μm−1 (at 10 μA cm−2) and threshold field of 4.62 V μm−1 (at 1 mA cm−2), which are lower than those of the MWCNT film. The a-CNP/MWCNT film can be deposited simply with large areas and may be a promising cathode material applied in field emission displays.

Dynamic Correlation Function of Monodispersed Colloid

Diffusive behaviors for two-dimensional (2D) monodispersed polystyrene array of droplet spreading by either methanol or ethanol suspension are observed on a rigid surface. Methanol solution can spread speedily on the glass surface because of the positive spreading coefficient. Conversely, the ethanol will not easily proliferate out. Monodisperse polystyrene particles are involved in Brownian motion in a thick layer during alcohol evaporation. A monolayer dimension of the drop has been developed at the final spreading. Lateral capillary forces are produced and caused the aggregation of particles. Evaporation at the edge of the ethanol film did not lead to the film to retract. The formation of 2D array, which preceded the spreading of the microscopic droplet across the surface, is able to indicate the dense structure to the dynamic correlation function.