Liquid Diffusion Research Articles

Mathematical representation of liquid jet diffusion characteristics effected with evaporation process in supersonic crossflow

The liquid jet diffusion characteristics effected with evaporation process and the mathematical representation of penetration depth in supersonic crossflow were discussed in this paper. A series of numerical simulations were carried out in both cold inflow (Tt = 300 K) and high enthalpy inflow (Tt = 1680 K). Based on the Euler-Lagrange method, the evaporation and diffusion process of liquid kerosene under different inflow conditions were studied. The mathematical representation of kerosene vapor penetration depth was obtained by convolution method. By analyzing the influence of different evaporation processes on the penetration depth of kerosene vapor, the penetration law of kerosene vapor with evaporation was revealed. The results show that the penetration process of kerosene is not only affected by the injection momentum ratio, but also the evaporation momentum ratio is an important factor affecting the penetration depth. The total penetration depth of kerosene vapor is composed of liquid kerosene penetration and penetration gain due to kerosene evaporation. And the mathematical expression of quantitative analysis was obtained by derivation. Making the local evaporation momentum of kerosene evenly distributed, extending the action distance and expanding the evaporation range are important ways to increase the penetration depth. The investigation in this paper plays an important role in explaining the diffusion mechanism and quantitative analysis of kerosene vapor with evaporation.

Removal of tetracycline in aqueous solution by iron-loaded biochar derived from polymeric ferric sulfate and bagasse.

In this study, the tetracycline (TC) removal performance of iron-loaded biochar (BPFSB) derived from sugarcane bagasse and polymerized iron sulfate was investigated, and the mechanism of TC removal was also explored by study of isotherms, kinetics and thermodynamics and characterization of fresh and used BPFSB (XRD, FTIR, SEM and XPS). The results showed that under optimized conditions (initial pH 2; BPFSB dosage 0.8g·L-1; TC initial concentration 100mg·L-1; Contact time 24h; temperature 298K), the removal efficiency of TC was as high as 99.03%. The isothermal removal of TC followed well the Langmuir, Freundlich, and Temkin models, indicating that multilayer surface chemisorption dominated the TC removal. The maximum removal capacity of TC by BPFSB at different temperatures was 185.5mg·g-1 (298K), 192.7mg·g-1 (308K), and 230.9mg·g-1 (318K), respectively. The pseudo-second-kinetic model described the TC removal better, while its rate-controlling step was a combination of liquid film diffusion, intraparticle diffusion, and chemical reaction. Meanwhile, TC removal was also a spontaneous and endothermic process, during which the randomness and disorder between the solid-liquid interface was increased. According to the characterization of BPFSBs before and after TC removal, H-bonding and complexation were the major interactions for TC surface adsorption. Furthermore, BPFSB was efficiently regenerated by NaOH. In summary, BPFSB had the potential for practical application in TC removal.

Potential removals of tetracycline and sulfamethoxazole by iron-loaded sludge biochar

In this study, the potential of iron-loaded sludge biochar (ISBC) to remove tetracycline (TC) and sulfamethoxazole (SMX) was investigated. Under the optimized conditions (initial pH of 4 and 5, ISBC dose of 1.0 g/L, contact time of 720 min, and temperature of 298 K), the maximum removal capacity of ISBC for TC and SMX was 81.04 mg/g and 80.19 mg/g, respectively. The better simulations of TC and SMX removal by Langmuir model and pseudo-second-order kinetic model indicated that monolayer chemisorption dominated their removal. Their removal rates depended on liquid film diffusion, intraparticle diffusion and chemical reactions. Moreover, their removal was a spontaneous and endothermic process with increasing randomness between the solid-liquid interfaces. Besides, their removal likely included two simultaneous pathways: adsorption/surface degradation and degradation/adsorption/surface degradation. Furthermore, ISBCs could be effectively desorbed and regenerated by ultrapure water and NaOH. In summary, ISBCs had the potential to be practically applicable for TC and SMX removal.

Liquid handling properties of carboxymethyl modified chitosan nonwovens for medical dressings

Chitosan (CS) is known to have excellent antibacterial, anti-inflammatory and hemostatic properties, while its liquid handling performances are dissatisfactory, making it hard to maintain a moist environment as wound dressings. In this study, the carboxymethyl chitosan (CMCS) needle-punched nonwovens were prepared by chloroacetic acid method. The structure and properties of CS and CMCS nonwovens were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), mass per unit area and thickness. Moreover, the liquid handling properties, including liquid absorption, retention, diffusion and contact angle were further investigated. The optimal parameters for carboxymethyl modification were explored via orthogonal experiments. Results demonstrated that CMCS nonwovens were successfully prepared, and the optimal conditions for carboxymethyl reaction were NaOH concentration of 30%, NaOH to chloroacetic acid molar ratio of 5:1, and etherification time of 4 h. The liquid absorption, retention, diffusion and hydrophilic properties of CMCS nonwovens were evidently enhanced compared with pristine CS nonwovens. Owing to the outstanding liquid handling properties, the proposed CMCS nonwovens might have potential application as medical dressings.

Microwave irradiation for the recovery enhancement of fly ash components: Thermodynamic and kinetic aspects

This study investigated the use of microwave-assisted leaching to recover the vanadium (V) and nickel (Ni) of fly ash collected from power plants. The fly ash sample was characterized using XRF, ICP-OES, powder X-ray diffraction, FESEM, and a laser particle size analyzer. The sample was found to be valuable as well as hazardous due to the presence of a considerable amount of base and heavy metals with an 80% passing particle size of 70 micrometers. Conventional leaching tests were performed using sulfuric acid (H2SO4), which resulted in 91.2% V, 80.5% Ni, and 57.6% Fe recoveries. Full recovery of the aforementioned components was achieved by adding 10% v/v hydrogen peroxide (H2O2). Microwave-assisted leaching showed promise, with comparable recoveries for Ni and V (complete recovery) at a microwave power of 700 W and a retention time of 30 mins, without the addition of any chemical additive. The study provided thermodynamic and kinetic justification for the efficient dissolution of V and Ni, which occurs via rapid boiling of the sulfuric acid solution (19.5% v/v) overcoming the chemical and liquid diffusion kinetic barriers. This work concludes that microwave-assisted leaching is an effective method for recovering heavy metals from fly ash samples as a complex solid waste.

Estimation of the drying process in porous media using the parallel and series moisture transfer model

Moisture transfer is a very common phenomenon in a wide range of engineering fields, such as civil engineering (cement-based constructions), food processing, mining and soil penetration, drying and imbibition of porous media (including phase change materials), etc. Based on the diffusion assumptions, the classical adopted model (especially for drying) is completed by the liquid permeation. However, it is still inadequate to compromise the complexity of the porous structures. In this work, we propose a “parallel -series assumption” of moisture transferring pattern, comprising different forms of moisture presence and the coupling styles, achieved by an interpolation factor to cover all the possible contribution ratios of the two patterns. Experimentally, we perform the drying of low porosity material under two ambient conditions over 160 days on both local and global parameters, ie., relative humidity (RH) and mass loss (ML). In the simulation part, a nonlinear diffusion-drying model containing liquid permeation and vapor diffusion in the transfer mechanism is applied to estimate the drying process, and compared with the experiment data. Results show different tendency for the two cases of either the permeation dominating case or the no-dominating case. This approach also clarifies the transition from evaporation of weak permeability for vapor diffusivity (square root behavior) towards the linear and faster behavior, which is observed in more porous and permeable materials for the vapor diffusion.

Recycling of cotton apparel waste and its utilization as a thermal insulation layer in high performance clothing

Recycling and converting textile waste into value-added products with enhanced functional properties pave the way toward a circular economy for sustainability. This research investigates the utilization of recycled cotton fiber from apparel cutting waste for fabricating high-performance thermal barrier fabrics. The physical characterization of the developed fabrics revealed a regular arrangement of fibers, consequently the uniform thickness of the fabric with no distortion on fiber surfaces due to the recycling operation of cotton waste. The developed fabrics also demonstrated a high softness index and low compression and bending average rigidity compared to the commercial fabric with similar thickness. The heat protection performance revealed an increase in fabric conductive and radiative heat resistance with increasing the amount of recycled cotton fiber in the fabrics. The inherent thermal resistance of cotton fiber and the low inter-fiber spacing because of their uniform orientation in the fabric lead to the high thermal resistance of developed fabrics. In the case of fabric air permeability concerning the clothing thermal comfort, no significant difference in breathability was observed among the test specimens. Besides, the moisture management profile of developed fabrics indicated the capability to create favorable thermal comfort within the clothing-skin microenvironment because of improved liquid transportation and diffusion of perspiration vapor through the fabric.

Removal Performance and Mechanism of Potassium Permanganate Modified Coconut Shell Biochar for Cd(Ⅱ) and Ni(Ⅱ) in Aquatic Environment

In this study, coconut shell biochar modified by KMnO4 (MCBC) was used as the adsorbent, and its removal performance and mechanism for Cd(Ⅱ) and Ni(Ⅱ) were discussed. When the initial pH and MCBC dosage were separately 5 and 3.0 g·L-1, respectively, the removal efficiencies of Cd(Ⅱ) and Ni(Ⅱ) were both higher than 99%. The removal of Cd(Ⅱ) and Ni(Ⅱ) was more in line with the pseudo-second-order kinetic model, indicating that their removal was dominated by chemisorption. The rate-controlling step for Cd(Ⅱ) and Ni(Ⅱ) removal was the fast removal stage, for which the rate depended on the liquid film diffusion and intraparticle diffusion (surface diffusion). Cd(Ⅱ) and Ni(Ⅱ) were mainly attached to the MCBC via surface adsorption and pore filling, in which the contribution of surface adsorption was greater. The maximum adsorption amounts of Cd(Ⅱ) and Ni(Ⅱ) by MCBC were individually 57.18 mg·g-1 and 23.29 mg·g-1, which were approximately 5.74 and 6.97 times that of the precursor (coconut shell biochar), respectively. The removal of Cd(Ⅱ) and Zn(Ⅱ) was spontaneous and endothermic and had obvious thermodynamic characteristics of chemisorption. Cd(Ⅱ) was attached to MCBC through ion exchange, co-precipitation, complexation reaction, and cation-π interaction, whereas Ni(Ⅱ) was removed by MCBC via ion exchange, co-precipitation, complexation reaction, and redox. Among them, co-precipitation and complexation were the main modes of surface adsorption of Cd(Ⅱ) and Ni(Ⅱ). Additionally, the proportion of amorphous Mn-O-Cd or Mn-O-Ni in the complex may have been higher. These research results will provide important technical support and theoretical basis for the practical application of commercial biochar in the treatment of heavy metal wastewater.

Experimental study on hygrothermal properties of recycled aggregate concrete

Recycled aggregate concrete has great significance from the environmental protection perspective. However, the current research findings on its hygrothermal properties are sparse. In this study, the apparent density, thermal conductivity, mass moisture content, water vapor permeability coefficient, water absorption coefficient, and liquid water diffusion coefficient of recycled aggregate concrete were determined by experimental methods. The effect of temperature and humidity on thermal conductivity was also studied. Furthermore, the fitting relations of the thermal conductivity of recycled aggregate concrete with the two variables of temperature and relative humidity were presented. The isothermal moisture absorption curve and the fitting relationship of water vapor permeability coefficient with relative humidity were also developed. The results indicate that the thermal conductivity of the eight recycled concrete specimens in the dry state at 25°C ranges from 0.994 to 1.242 W/(m·K). The thermal conductivity increases with the increase in temperature. When the temperature rises from 25°C to 35°C, the thermal conductivity of recycled aggregate concrete increases by 3.8%–13.5%. With the increase of relative humidity, the thermal conductivity of recycled aggregate concrete shows an increasing trend, followed by a steady state, and finally the increasing trend, showing a cubic function relationship between them. When the relative humidity increases from 0% to 95%, the thermal conductivity increases by about 20%. The mass moisture content and the water vapor permeability coefficient increase with relative humidity. The results of this study can provide basic information for the study on the heat and moisture transfer of recycled aggregate concrete, and enhance the database of hygrothermal properties of building materials.

Wound healing and the quantum nature of viscosity and thermal diffusion of liquids

In wound healing the viscosity of the ointment and its thermal diffusion are important. However, both the viscosity and thermal diffusion of liquids are quantum in nature and require quantum description. It comes from the way the material world was created. The whole material world was created by Black Holes of anti-matter and the NEMF that separated the matter from the anti-matter got imprinted on all material creations. This automatically explains: 1/ why the particles are particles and waves at the same time; 2/ why at very low temperatures (close to the absolute Zero (-273 0 K)) when the particles don’t have energy to spin, they behave like waves; and 3/ why the viscosity and thermal diffusion of liquids have quantum nature.

Approach to hyperuniformity in a metallic glass-forming material exhibiting a fragile to strong glass transition

We investigate a metallic glass-forming (GF) material (Al90Sm10) exhibiting a fragile-strong (FS) glass-formation by molecular dynamics simulation to better understand this highly distinctive pattern of glass-formation in which many of the usual phenomenological relations describing relaxation times and diffusion of ordinary GF liquids no longer apply, and where instead genuine thermodynamic features are observed in response functions and little thermodynamic signature is exhibited at the glass transition temperature, Tg. Given the many unexpected similarities between the thermodynamics and dynamics of this metallic GF material with water, we first focus on the anomalous static scattering in this liquid, following recent studies on water, silicon and other FS GF liquids. We quantify the “hyperuniformity index” H of our liquid, which provides a quantitative measure of molecular “jamming”. To gain insight into the T-dependence and magnitude of H, we also estimate another more familiar measure of particle localization, the Debye–Waller parameter 〈u2〉 describing the mean-square particle displacement on a timescale on the order of the fast relaxation time, and we also calculate H and 〈u2〉 for heated crystalline Cu. This comparative analysis between H and 〈u2〉 for crystalline and metallic glass materials allows us to understand the critical value of H on the order of 10–3 as being analogous to the Lindemann criterion for both the melting of crystals and the “softening” of glasses. We further interpret the emergence of FS GF and liquid–liquid phase separation in this class of liquids to arise from a cooperative self-assembly process in the GF liquid.Graphical abstract

Nb Phase Position Marking for Clarifying the Formation Process of Cu-Al Composite Interfacial Phases in Continuous Composite Casting

Cu-Al composites are widely applied materials exhibiting advanced properties of both matrix metals. Controlling the brittle interfacial phases is a key factor in improving the interfacial strength of Cu-Al composites. This paper studied the interfacial formation process of Cu-Al composites fabricated by continuous composite casting. The phase formation sequence, growth direction and formation mechanism were clarified via element marking and thermodynamic calculations. The spatial distribution of the interfacial phases from the aluminum side to the copper side is as follows: the α + θ layer (α-Al + CuAl2), the θ layer (CuAl2) and the γ layer (Cu9Al4). Moreover, insular η phases (CuAl) and δ phases (Cu3Al2) exist in the γ phase sublayer. The formation sequence of interfacial phases is as follows: the θ phase, the η phase, the δ phase and the γ phase. The θ layer and α + θ layer are transformed from a liquid diffusion layer formed by scouring the surface of copper with liquid aluminum, the η and δ phases grow towards the θ layer and the γ phase simultaneously grows towards both the copper matrix and the θ layer.

Preparation of PLA/PEG@SDS microfibers‐based nonwovens via melt‐blown process parameters: Wound dressings with enhanced water wetting performance

AbstractPolylactic acid (PLA) melt‐blown nonwovens are promising materials for medical and healthcare applications due to their properties such as softness, breathability, biodegradability, and biocompatibility. However, their widespread commercial application has been limited by their poor mechanical properties and insufficient hydrophilicity limit. To address these limitations, we prepared polylactic acid/polyethylene glycol@sodium dodecyl sulfate (PLA/PEG@SDS) microfibers‐based nonwovens using a melt‐blown process. The average fiber diameter of PLA/PEG@SDS microfibers nonwovens could be tuned from 1 to 13.9 μm by regulating the die temperature or hot air pressure. In addition, increasing the die temperature from 210°C to 225°C resulted in a 140.3% and 124.8% increase in the breaking resistance along the mechanical direction (MD) and transverse direction (CD), respectively. Meanwhile, the increase in the breaking resistance was observed between the hot air pressure and the mechanical strength of the PLA/PEG@SDS microfibers‐based nonwovens. Notably, the prepared samples exhibited a short wetting time of 3.438 s, a fast water absorption rate of 68.401%·s−1, and an excellent liquid water diffusion of 5.86 mm s−1. These results suggest that the PLA/PEG@SDS microfibers nonwovens prepared using melt‐blown process demonstrate efficient wetting performance, which paves the way for the industrial production of medical‐grade materials such as wound dressings.

Liquid Superspreading on Surface with Microhexagonal Structure Inspired by Rock‐Climbing Fish

The dynamic spreading mechanism of liquid on a specific surface is vital for understanding interface wetting and antifouling. Whereas, how to control the spreading process and accelerate the spreading speed is a major challenge. The rock‐climbing fish is characterized by its alepidote feature that lives in stream habitats dominated by strong currents. The mucus on its body surface plays a vital role in its adherence and maintenance of antifouling and antibacterial properties. However, the rapid, uniform, and efficient spreading mechanism of mucus on the fish body surface remains largely unknown. Herein, it is revealed that the surface of the rock‐climbing fish is overlaid fully by the microhexagonal texture structure. This hexagonal structure shows a superspreading effect on liquid diffusion, resulting from testing with bionic microfabrication inspired by the rock‐climbing fish. It is demonstrated that the microhexagonal‐textured surface can enhance liquid spreading quickly and evenly on the surface by regulating the moving contact line of the liquid. This kind of superspreading mechanism has great potential applications in the antifouling, electroencephalogram electrode interfaces, flexible skin sensors, and interfacial lubrication of underwater surfaces.

Adsorption of BEZAKTIV BLAU V3-R and BEZAKTIV BLAU S-2R reactive dyes onto rice husk modified by the circular economy concept

Rice husk, modified with effluent from the alkaline scouring of cotton, employing an inexpensive treatment based on the circular economy concept, is used as a bio-sorbent to study the equilibrium and kinetic on cold brand BEZAKTIV BLAU V3-R (BBV3-R) and medium brand BEZAKTIV BLAU S-2R (BBS2-R) reactive dyes. 10, 20, and 40 g L−1 rice husk is used to follow adsorption of 0.1, 0.2, 0.3, 0.4, and 0.5 g L−1 BBV3-R and BBS2-R in a presence of 60 g L−1 NaCl at pH 10, at the temperature of 25 °C and 40 °C, respectively. Langmuir, Freundlich, and Dubinin-Radushkevic's adsorption models were employed, with the Freundlich model proving the best fit for our data. Activation energy calculated with the Dubinin–Radushkevic model (lower than 8 kJ mol−1) confirms the physical sorption of these reactive dyes onto the husk. The obtained maximum experimental absorption capacities of 122.2 mg g−1 for BBV3-R and 171.7 mg g−1 for BBS2-R using 10 g L−1 ERH are the best found in the literature. Pseudo-second-order model determines the adsorption kinetics, while the liquid film diffusion model is rate-determining. This paper demonstrates the applicability of the circular economy concept to obtain an efficient adsorbent for purifying colored effluent enriched with reactive dyes, which are one of the most challenging dyes in the textile industry from the aspect of their effluent purifying.

Preparation of Nanoparticles and Diffusion Behavior of Metal Ions in Ionic Liquids

Ionic liquids (ILs) have attracted much attention as tunable liquids because of their unique structures and properties. However, the mechanisms of chemical reactions and solute diffusion in ionic liquids are still unknown. This article summarizes our previous studies and recent results on the mechanisms of metal particle formation and solute diffusion in ionic liquids, focusing on the local structure of ionic liquids. It was found that the shape and size of metal particles formed in ionic liquids using electron beams or X-rays are strongly influenced by the local structure. In the study of the diffusion behavior of metal ions in ionic liquids, we proposed a hopping-like diffusion model and proposed that this behavior could be strongly influenced by local structures such as hole concentration and/or domain structures.

Theoretical modeling of diffusion clouds of liquid hydrogen spilling in crosswind field with atmospheric inversion layer

A theoretical model was developed to predict the diffusion process of hydrogen clouds in a crosswind field with an atmospheric inversion layer in this work to evaluate the safety of liquid hydrogen spills. The theoretical model was verified by the experimental results carried out by NASA. The results show that the maximum deviation of diffusion cloud centerline heights of the theoretical model and experiments is 8.92%. The mechanism of the inversion layer suppressing cloud rise is revealed from the theoretical model, atmospheric temperature gradient is closely related to the air density gradient. Compared to the case without atmospheric inversion layer, the cloud height decreases by 2.60%, 5.22%, and 8.70% and the cloud concentration increases by 6.20%, 12.78%, and 22.30% for the temperature gradient of 0.03, 0.06 and 0.10 K/m, respectively. The velocity of crosswind is 1.7 m/s, 2.7 m/s, 3.6 m/s, and 6.0 m/s in the temperature gradient of 0.10 K/m inversion layer environment, the height of the cloud is 34.77 m, 24.05 m, 16.83 m, and 11.16 m, and the hydrogen concentrations of the cloud centerline are 10.22%, 13.67%, 17.54%, and 28.92%, respectively. Therefore, it is significant to consider the crosswind field and atmospheric inversion layer for liquid hydrogen diffusion.

Directional regulation and mechanism analysis of the surface properties of hydrothermal carbon by circulating liquid in the hydrothermal carbonization procedure

The complexity of the chemistry behind the hydrothermal conversion is enormous. Components interact with their own physical and chemical structure, making it harsh to understand the conversion as a whole. Herein, the six-water recirculation and loading nano SiO2 experiment in a one-pot hydrothermal carbonization procedure was designed to elucidate the mechanism of regulating the functional groups and microporous structure of the hydrochar surface. The hydrochar prepared by the second circulating liquid and loading nano-SiO2 (HBC-R2/Si) was equipped most enriched functional groups (carboxyl = 11.48 μmol/g, phenolic hydroxyl = 52.98 μmol/g, lactone groups = 46.52 μmol/g) and suitable pore size (1.90 nm–1.93 nm) as a sorbent riched in hemicellulose. The sorption kinetics (equilibrium reached ≈ 480 min) are approximately evenly fitted by the pseudo-second-order, Weber and Morris, and Elovich models, indicating that membranes and particles diffusion, pore diffusion, and surface sorption coexisted in the sorption of methylene blue (MB) on the hydrochar materials. Simultaneously, all hydrochar materials achieved over 25% MB removal within 90 min (liquid membrane diffusion) and over 40% for HBC-R2 and HBC-R2/Si, suggesting that liquid membrane diffusion is the predominant rate-limiting step. Pearson's correlation analysis and Mantel's analysis announced that the cation exchange capacity (CEC), pore size, and carboxyl groups on the hemicellulose affect the sorption capacity by limiting the pore diffusion procedure. However, the CEC and the phenolic hydroxyl groups on the cellulose and hemicellulose affect the sorption rate by limiting membrane diffusion. Three consecutive sorption/desorption cycles confirmed the high stability and reusability of HBC-R2/Si composites.

Potassium Hydroxide Activation as an Adsorbent for Kinetic Models of Hexavalent Chromium Adsorptions onto <i>Garcinia mangosteen</i> Shell

The utilized adsorption kinetic models, i.e., pseudo-zero order, pseudo-first-order, pseudo-second order, intraparticle diffusion, Bangham’s pore diffusion, liquid film diffusion, modified Freundlich and Elovich models have been cultivated the hexavalent chromium adsorption process. A high correlation coefficient (R2) and a small residual root mean square error (RMSE) and Chi-square (χ2) can be depicted in the pseudo-first order for the kinetic adsorption process of hexavalent chromium adsorption on the activated mangosteen shell with potassium hydroxide and carbonized at 400 °C for 2 h as a biochar adsorbent which has a specific surface area of 164 m2/g.

Liquid Structures and Diffusion Dynamics of Alkyl-Pyrene Liquids Studied by Molecular Dynamics Simulations.

Functional molecular liquids (FMLs) based on alkylated π-conjugated molecules have attracted attention as solvent-free and nonvolatile liquid materials with prominent optoelectronic features. Recently, novel FML compounds containing pyrene as the functional core were synthesized, and their rheological and photochemical properties were investigated. Although the molecules differ only in the number of alkyl chain substituents and their substitution positions, their viscosity coefficients are largely different beyond the Stokes-Einstein relation on the assumption of identical microscopic friction, indicating that local microscopic molecular interactions are crucial for the macroscopic rheological properties. Here, we report a theoretical study on the rheological properties of the alkyl-pyrene liquids by means of atomistic molecular dynamics (MD) simulations. We performed long-time MD simulations for tens of microseconds to obtain ample statistical samples of the alkyl-pyrene liquids and analyzed their liquid structures and diffusion dynamics based on spatiotemporal correlation functions. We found the formation of characteristic local liquid structures of π-π stacking of the pyrene moieties and locally anisotropic and anomalous diffusion dynamics, which remarkably vary depending on the alkyl substituent patterns. The present results provide an atomistic insight into the macroscopic rheological properties of alkyl-π FMLs and molecular design strategy for them.