Larger Pore Diameter Research Articles

A review of zeolitic imidazolate frameworks (ZIFs) as electrochemical sensors for important small biomolecules in human body fluids.

Small biomolecules play a critical role in the fundamental processes that sustain life and are essential for the proper functioning of the human body. The detection of small biomolecules has garnered significant interest in various fields, including disease diagnosis and medicine. Electrochemical techniques are commonly employed in the detection of critical biomolecules through the principle of redox reactions. It is also a very convenient, cheap, simple, fast, and accurate measurement method in analytical chemistry. Zeolitic imidazolate frameworks (ZIFs) are a unique type of metal-organic framework (MOF) composed of porous crystals with extended three-dimensional structures. These frameworks are made up of metal ions and imidazolate linkers, which form a highly porous and stable structure. In addition to their many advantages in other applications, ZIFs have emerged as promising candidates for electrochemical sensors. Their large surface area, pore diameter, and stability make them ideal for use in sensing applications, particularly in the detection of small molecules and ions. This review summarizes the critical role of small biomolecules in the human body, the standard features of electrochemical analysis, and the utilization of various types of ZIF materials (including carbon composites, metal-based composites, ZIF polymer materials, and ZIF-derived materials) for the detection of important small biomolecules in human body fluids. Lastly, we provide an overview of the current status, challenges, and future outlook for research on ZIF materials.

Pore Structure and Fractal Characteristics of Continental Low Maturity Organic-Rich Shale in the Sha-4 Member of the Liaohe Western Depression

The research on pore structure and heterogeneity of shale reservoirs has always been a hotspot in the study of unconventional reservoir characteristics. China is a country dominated by continental shale. Compared with marine shale, continental shale has lower maturity and stronger reservoir heterogeneity. In this study, Sha-4 shale in the Liaohe Western Depression was selected for low-temperature nitrogen adsorption, scanning electron microscopy and other experiments revealing the pore structure and fractal characteristics of continental low mature organic-rich shale. The fractal dimension was calculated by the FHH model and the effects of TOC and mineral composition on pore structure and fractal characteristics were discussed. The results show that the Sha-4 shale in the study area is mainly mesoporous and the main pore types are inorganic pores with relatively large pore diameters, such as intergranular pores and inter-crystalline pores. The pore morphology is very complex, mainly narrow slit and flat pore, and the pore is often filled with organic matter. The fractal dimensions D1 range from 2.58 to 2.87 and D2 range from 2.18 to 2.55, and the pore structure shows obvious dual fractal characteristics. The pore structure and fractal characteristics of shale are mainly affected by TOC and quartz due to the low degree of the thermal evolution of shale and their effects are different from those of marine shale reservoirs. The increase in TOC reduces the heterogeneity of the shale reservoir. In addition, mineral particles with strong weathering resistance and stability such as quartz can protect the pore structure of shale, improve the pore structure and reduce the reservoir heterogeneity. This study can provide support for the study of low maturity continental shale reservoir heterogeneity in the Sha-4 member of the Liaohe Western Depression.

A Model of Stress-Damage-Permeability Relationship of Weakly Cemented Rocks under Triaxial Compressive Conditions.

To unravel the permeability variation mechanism of weakly cemented rocks (WCR), the paper conducted triaxial permeability tests on weakly cemented sandstones (WCS) collected from the Jurassic formation in northwest China. The paper identified the correlation of WCS permeability versus porosity, cementation structure, and mineral composition, further developing a model to characterize the WCS stress-damage-permeability relationship. The research indicated that the WCS permeability was initially high due to the naturally high porosity, large pore diameter, and loose particle cementation, thus favoring a significant decline as pore convergence in the compaction stage. In the residual stage, kaolinite and montmorillonite minerals disintegrated into water and narrowed fractures, causing a slight permeability increase from the initial to the maximum and residual stages. The WCS matrix fracturing was phenomenologically accompanied by clay mineral disintegration. By assuming that the matrix can be compressed, jointed, and fractured, the paper defined a damage variable D and accordingly developed a stress-damage-permeability relationship model that incorporated matrix compression, jointing, and fracturing. The model can describe the WCS permeability regime regarding the high initial permeability and slight difference of the maximum and residual permeabilities versus the initial.

Organic mesoporous silica with variable structures for pH-Stimulated antitumor drug delivery

Hollow (hollow periodic mesoporous organosilica, HPMO), core-shell (mSiO2@PMO), and bowl (nanobowl periodic mesoporous organosilica, BPMO) organic mesoporous silica nanoparticles were produced in this work. According to adsorption and desorption studies, all three have large pore diameters (2–10 nm), high specific surfaces (567–726 m2g-1), and large pore volumes (0.4–1.4 cm3g-1). After transporting the antitumor pharmaceutical doxorubicin (DOX) and ZnO-controlled pH stimulation response modification, the obtained DOX@PMOs@ZnO has a high drug loading rate (17–37%, with the largest drug loading capacity up to 378 μg/mg). Cell uptake and apoptosis tests revealed that the three morphologies of DOX@PMOs@ZnO had high cellular uptake and inhibitory effects. These results showed that the DOX@PMOs@ZnO preparation may be beneficial for tumor-targeted therapy. More importantly, when three unique morphologies of DOX@PMOs@ZnO were analyzed in terms of drug loading, cell uptake, and apoptosis, the findings showed that the hollow structure of DOX@HPMO@ZnO and the bowl-like structure of DOX@BPMO@ZnO had more substantial impacts in all areas.

Electrospun chitosan nanofiber constructing superhigh-water-flux forward osmosis membrane

Forward osmosis (FO) technology exhibits great potential in seawater desalination and wastewater treatment due to its negligible energy consumption and high antifouling, however, the weak desalination capability, especially low water flux, remains challenging. Herein, a cost-effective and high-desalination-performance chitosan (CS)-based FO membrane is developed via coupling the electrospinning CS nanofibers and interfacial-polymerized polyamide (PA). The electrospun nanofibers construct the porous and hydrophilic CS layer with the large pore-diameter of ~274 nm and low thickness of ~10 μm, enabling the effective transport of water molecules, specifically, a superhigh water flux of 107.53 LMH at a low salt-water ratio of 0.24 g·L−1. In addition, such superior desalination performance of the as-prepared FO membrane is universal for the various salt species and concentrations. Our CS nanofiber-based membrane with the high separation capability of water-salt, desirable antibacterial activity, as well as the low cost, offers a roadmap toward the sustainable membrane materials.

Metal Oxyhydroxide Catalysts Promoted CO2 Absorption and Desorption in Amine-Based Carbon Capture: A Feasibility Study.

The huge energy penalty of CO2 desorption is the greatest challenge impeding the commercial application of amine-based CO2 capture. To deal with this problem, a series of metal oxide and oxyhydroxide catalysts were synthesized in this study to kinetically facilitate the CO2 desorption from 5.0 M monoethanolamine (MEA). The effects of selected catalysts on CO2 absorption kinetics, CO2 absorption capacity, CO2 reaction enthalpy, and desorption duty reduction of 2.0 M MEA were investigated by a true heat flow reaction calorimeter to access the practical feasibility of the catalytic CO2 desorption. The kinetic study of catalytic CO2 desorption was also carried out. CO2 desorption chemistry, catalyst characterization, and structure-function relationships were investigated to reveal the underlying mechanisms. Results show that addition of the catalyst had slight effects on the CO2 absorption kinetics and CO2 reaction enthalpy of MEA. In contrast, the CO2 desorption efficiency greatly increased from 28% in reference MEA to 52% in ZrO(OH)2-aided MEA. Compared to the benchmark catalyst HZSM-5, ZrO(OH)2 exhibited a 13% improvement in CO2 desorption efficiency. More importantly, compared to the reference MEA, the CO2 desorption duties of ZrO(OH)2 and FeOOH-aided MEA significantly reduced by 45 and 47% respectively, which are better than those of most other reported catalysts. The large surface area, pore volume, pore diameter, and amount of surface hydroxyl groups of ZrO(OH)2 and FeOOH afforded the catalytic performance by promoting the adsorption of alkaline speciation (e.g., MEA and HCO3 -) onto the particle surface.

Salt migration and capillary absorption characteristics of cement mortar partially immersed in NaCl solution

Salt crystallization represents a major reason for the damage observed for porous building materials in humid coastal areas. Despite the several theories developed to explain the process, no unanimous opinion has been proposed for the mechanism underlying the damage. A better understanding of the migration, crystallization, and distribution of salts in porous building materials in the presence of water is thus warranted to improve the durability for cultural heritages and new buildings. This paper reports an experimental study of crystal distribution, micromorphology, chloride ion migration, pore structures, and capillary absorption behaviors of cement-mortar specimens (side-coated and side-uncoated) at three different water-cement ratios (0.4, 0.6, and 0.8) after 120-day partial immersion in 5 wt% NaCl solution. Results showed that the different pore characteristics and side-coating treatment of the specimens governed not only capillary absorption, but also salt migration and distribution. The specimens with a large average pore diameter and greater porosity yielded more external salt crystals, while those with a small average pore diameter and dense surfaces demonstrated the reverse. For vertical migration, the Cl− concentration changed slightly with height of the specimens, except for the top segment. For horizontal migration, the Cl− concentrations in the central samples were higher than the edge samples. Of note, the side-coated specimens were associated with reduced external salt crystals and lower Cl− concentration in their edge samples. Compared with the salt-free specimens, both the capillary absorption coefficient (Acap) and capillary moisture content (Wcap) of the salt-contaminated specimens were lower (water-cement ratio = 0.6, −45.72%, −56.39%; water-cement ratio =0.8, −60.8%, −56.34%), illustrating the inhibitory effect of salt crystallization on the hygroscopic properties of the porous materials. Lastly, both the Acap and Wcap of the side-coated specimens were lower than uncoated ones.

Dual template using P123-gelatin for synthesized large mesoporous silica for enhanced adsorption of dyes

Mesoporous Silica with a large mesopore channel was synthesized using the sol-gel method for dye adsorption. A dual template consisting of P123 and gelatin at different ratios was employed in the sol-gel synthesis to enhance surface area and mesopore diameter. Gelatin is a green pore directing agent that strengthens P123 thermal stability during the calcination of silicate gel. Optimization of P123:gelatin ratio to 1:0.02 increased the surface area of mesoporous silica to 561.9 m2/g and expanded the pore diameter to 10 nm. The large pore diameter and surface area enhanced methylene blue adsorption capacity to 363.63 mg/g. The adsorption of methylene blue on mesoporous silica follows the pseudo second-order kinetic and the Langmuir model. Regeneration studies using thermal and chemical treatments exhibited the potential of mesoporous silica as an adsorbent for multiple adsorption-desorption of dyes.

Reservoir Characteristics and Resource Potential of Marine Shale in South China: A Review

Many sets of Paleozoic marine organic-rich shale strata have developed in South China. However, the exploration and development results of these shale formations are quite different. Based on the data of core experiment analysis, drilling, fracturing test of typical wells, the reservoir differences and controlling factors of four sets of typical marine organic-rich shale in southern China are investigated. The four sets of shale have obvious differences in reservoir characteristics. Ordovician–Silurian shale mainly develops siliceous shale, mixed shale and argillaceous shale, with large pore diameter, high porosity, moderate thermal maturity, large pore volume and specific surface area. Cambrian shale mainly develops siliceous shale and mixed shale, with small pore diameter, low porosity, high thermal maturity and smaller pore volume and specific surface area than Ordovician–Silurian shale. Devonian–Carboniferous shale has similar mineral composition to Ordovician–Silurian shale, with small pore diameter, low porosity, moderate thermal maturity and similar pore volume and specific surface area to that of Cambrian shale. Permian shale has very complex mineral composition, with large pore diameter, low to medium thermal maturity and small specific surface area. Mineral composition, thermal maturity and tectonic preservation conditions are the main factors controlling shale reservoir development. Siliceous minerals in Cambrian shale and Ordovician–Silurian shale are mainly of biological origin, which make the support capacity better than Devonian–Carboniferous shale and Permian shale (siliceous minerals are mainly of terrigenous origin and biological origin). Thermal maturity of Ordovician–Silurian shale and Devonian–Carboniferous shale is moderate, with a large number of organic pores developed. Thermal maturity of Cambrian shale and Permian shale is respectively too high and too low, the development of organic pores is significantly weaker than the two sets of shale above. There are obvious differences in tectonic preservation conditions inside and outside the Sichuan Basin. Shale reservoirs inside the Sichuan Basin are characterized by overpressure due to stable tectonic activities, while shale reservoirs outside the Sichuan Basin are generally normal–pressure. Four sets of marine shale in South China all have certain resource potentials, but the exploration and development of shale gas is still constrained by complicated geological conditions, single economic shale formation, high exploration and development costs and other aspects. It is necessary for further research on shale gas accumulation theory, exploration and development technology and related policies to promote the development of China’s shale gas industry.

Experimental study on microstructure characteristics of saturated remolded cohesive soil during consolidation

In this paper, drained consolidation tests of saturated remolded cohesive soil were carried out at different loading rates, and the samples at different loading stages were measured by nuclear magnetic resonance (NMR) testing. Through qualitative analysis of the relationship between the transverse relaxation time T2, peak area and porosity, the deformation micro-response of the saturated remolded cohesive soil was studied. The results showed that the transverse relaxation time T2 of the saturated remolded cohesive soil samples during the initial stage consisted of two spectral peaks, representing pores with large and small pore diameters, respectively. As loading progressed, the pore diameters in each sample group gradually shifted to smaller sizes, and the final form of the T2 spectrum was unimodal, in which the pores became denser and more uniform. In the initial stage of loading, the T2 spectrum of the soil sample with faster loading showed no obvious change trend due to the influence of drainage lag. After a sufficiently long dead load time, the final shape of the T2 spectrum was very similar regardless of loading rate, indicating that the loading rate only affected the intermediate state of the soil sample, and the final state was determined by the initial state of the sample. At the same time, after a certain dead load time, the changes in pore diameter were no longer obvious, indicating that the flowing fluid in the pore was drained and that drainage consolidation was complete. According to the positive correlation between the loading rate and maximum pore pressure, a boundary rate was obtained. We could reasonably infer that if the controlled loading rate was less than this value, drainage consolidation was complete in the main consolidation stage.

Study on Pore Structure and Fractal Characteristics of Tar-Rich Coal during Pyrolysis by Mercury Intrusion Porosimetry (MIP)

This study aims to show how fractal analysis can be effectively used to characterize the pore structure of porous tar-rich coal. In this study, tar-rich coal pores were obtained by mercury intrusion porosimetry (MIP). The results showed that the sample had a high porosity and large pore diameter after pyrolysis, and the porosity of tar-rich coal was more than 35% at 600°C. The pore-throat ratio at high temperature was large, resulting in the high mercury retention rate. The pore distribution curves of samples at pyrolysis temperatures of 500 and 600°C were unimodal, and those of samples at room temperature and 150, 300, and 400°C were bimodal. The models for calculating fractal dimension based on MIP include Menger sponge model and thermodynamic model. Experiments show that the Menger sponge method is more reasonable when the pore size is less than 50 μm and greater than 350 nm. For the fractal dimension calculation of the whole pore curve section, the thermodynamic method was more reasonable. The use of fractal analysis in conjunction with the results of classical characterization methods leads to a better understanding of pore evolution in the pyrolysis process of tar-rich coal. The average fractal dimension could also be used as a valid parameter to monitor the textural evolution of the coals.

Organizations of melittin peptides after spontaneous penetration into cell membranes

The antimicrobial peptide, melittin, is a potential next-generation antibiotic because melittin can spontaneously form pores in bacterial cell membranes and cause cytoplasm leakage. However, the organizations of melittin peptides in cell membranes remain elusive, which impedes the understanding of the poration mechanism. In this work, we use coarse-grained and all-atom molecular dynamics (MD) simulations to investigate the organizations of melittin peptides during and after spontaneous penetration into DPPC/POPG lipid bilayers. We find that the peptides in lipid bilayers adopt either a transmembrane conformation or a U-shaped conformation, which are referred to as T- and U-peptides, respectively. Several U-peptides and/or T-peptides aggregate to form stable pores. We analyze a T-pore consisting of four T-peptides and a U-pore consisting of three U-peptides and one T-peptide. In both pores, peptides are organized in a manner such that polar residues face inward and hydrophobic residues face outward, which stabilizes the pores and produces water channels. Compared with the U-pore, the T-pore has lower energy, larger pore diameter, and higher permeability. However, the T-pore occurs less frequently than the U-pore in our simulations, probably because the formation of the T-pore is kinetically slower than the U-pore. The stability and permeability of both pores are confirmed by 300 ns all-atom MD simulations. The peptide organizations obtained in this work should deepen the understanding of the stability, poration mechanism, and permeability of melittin, and facilitate the optimization of melittin to enhance the antibacterial ability.

Features of the porous morphology of anodic alumina films at the initial stage of disordered growth

A characteristic feature of disordered porous anodic film growth at the initial stage of aluminum anodizing was revealed by varying the electrolyte type and anodizing voltage. The samples were obtained by the electrochemical oxidation of thin aluminum films (100 nm thick) on SiO2/Si substrates in a 0.3 M oxalic acid at 10–50 V and were studied by SEM. The ImageJ analysis of the images revealed the simultaneous development of two large groups of pores: major pores with a large diameter and minor pores with a smaller diameter. When anodizing in oxalic acid at 10–50 V, it has been shown that the ratio of the diameters of the major and minor pores remains constant and is about 1.17. Using a geometric model, we demonstrated that the centers of the minor pores are located inside the elementary hexagonal cell formed by the centers of the major pores. Moreover, our results are very close to the theoretical value of 2/√3. At the initial stage of disordered pore growth, the development of minor pores rather than major pores is not a random process and is determined by energy-efficient conditions for the development of pores inside the hexagonal cells formed by the major pores. The increase in compressive mechanical stress in the anodic film leads to an interruption in the development of such pores.

Chloride Ion Transport Properties in Lightweight Ultra-High-Performance Concrete with Different Lightweight Aggregate Particle Sizes.

In this paper, the microstructure and resistance to chloride ion penetration of ultra-high-performance concrete (UHPC) prepared from lightweight aggregate (LWA) were studied through simulation and experiment. The effects of LWA with different particle sizes on the chloride ion transport properties of lightweight ultra-high-performance concrete (L-UHPC) were discussed through simulation test results. The random delivery model of LWA in L-UHPC was established by MATLAB, and the model was introduced into COMSOL. Through the comparative analysis of experimental data and simulation results, the repeatability of the proposed model and the simulation accuracy were verified. The results show that when the LWA particle size changes from 0.15–4.75 mm to 0.15–1.18 mm, the width of interfacial transition zone (ITZ) and the overall porosity of L-UHPC decrease. This is because the large particle size LWA has more open pores with larger pore diameters and related interconnections, which are potential channels for chloride ion transport. Therefore, the chloride ion transport properties in L-UHPC are inhibited, which is manifested by the “tortuosity effect” of the LWA.

Effect of the pore architecture of Ziegler-Natta catalyst on its behavior in propylene/1-hexene copolymerization

The role of the pore architecture of the Ziegler-Natta (ZN) catalysts in the propylene polymerizations is unveiled, towards the catalyst activity, H2– and comonomer-response, and final properties of the synthesized polymer. In this regard, two commercially available ZN catalysts (Cat-A and Cat-B belong to the 4th generation, containing diisobutyl phthalate as internal donor) with a similar composition but with different pore structures were employed in propylene/1-hexene copolymerizations in the presence of H2 as a chain transfer agent. Although pore diameter does not alter H2-response noticeably, it significantly affects the comonomer incorporation as well as the distribution of the isotactic sequence length in the copolymer backbone. Cat-A with a lower surface area, a larger pore diameter, and a wider inlet showed slightly higher activities in homopolymerization and copolymerization experiments. According to the self-nucleation and annealing (SSA) results, the copolymer produced from Cat-A demonstrated lower isotactic sequence length and lamellar thickness contents owing to its larger pore diameter with wider inlets. Moreover, Temperature Rising Elution Fractionation (TREF) profiles asserted SSA data in which the copolymer from Cat-A represented a higher content of low elution temperatures fractions, due to its higher comonomer content. These findings will lead to catalysts for different polypropylene grades.

Catalytic Cracking of Waste Tires using Nano‐ZSM‐5/MgAl‐LDO

Catalytic cracking is a promising approach to realize the resource utilization of waste tires. Herein, a new composite catalyst, nano‐ZSM‐5/MgAl‐LDO, is synthesized, and catalytic cracking of waste tires over the composite catalyst is explored. Experimental results indicate that nano‐ZSM‐5/MgAl‐LDO composite catalyst is characterized by high dispersion of nano‐ZSM‐5 on the surface of LDO, large Brunauer–Emmett–Teller‐specific surface area, large pore diameter and volume, and suitable acid and basic properties. Moreover, not only does the nano‐ZSM‐5/MgAl‐LDO composite catalyst increase the conversion rate (62.04%) and degradation rate (1.33 × 10−3 s−1) of waste tires, but it also enhances the selectivity (33.32%) of light hydrocarbons in pyrolysis products, which was nearly 10% higher than that of thermal pyrolysis.

Effect of different lithological assemblages on shale reservoir properties in the Permian Longtan Formation, southeastern Sichuan Basin: Case study of Well X1.

Various types of marine-continental transitional facies are present in the gas-bearing shales of the southeastern Sichuan Basin. A review of the different lithological assemblages in these rocks is important for assessing the likely shale gas content and the development of the storage space. This study of the lithological assemblages of the Permian Longtan Formation in the southeastern Sichuan Basin at Well X1 used core observations, optical thin-section observations, Ar-ion polishing, scanning electron microscopy, and nitrogen adsorption tests to compare and analyze storage space types and pore structures in the shale to determine the sedimentary paleoenvironment, petromineralogy, and organic content. The marine-continental transitional facies in the study area were deposited in a warm climate that favored enrichment by organic matter. The kerogen is type II2-III (average vitrinite reflectance 2.66%), which is within the favorable thermal maturity range for the presence of shale gas. The lithology mainly consists of shale, siltstone, and limestone (with bioclasts), as well as a coal seam. The lithological development divides the Longtan Formation into lower (swamp), middle (tidal flat/lagoon), and upper (delta) sub-members. From lower to upper divisions, the lithofacies evolved from silty shale to clay shale and then to shale intercalated with siltstone or calcareous layers. The proportions of intergranular and dissolution pores in the clay minerals decrease gradually from lower to upper sub-members, and pore size sizes also tend to decrease. Relatively large-diameter pores and microfractures occur in the inorganic matter in the lowest sub-member. Quartz and clay are the main constituents of the shale, respectively contributing to the specific surface area and specific pore volume of the reservoir space.

Influence of calcination atmosphere on Fe doped activated carbon for the application of lead removal from water

In the current work, granular activated carbon (GAC) materials doped with 5 and 10 wt% of Fe were prepared via incipient wetness impregnation method utilizing two different solvents (water and ethanol) and calcined in N2 and static air atmosphere. The prepared materials were thoroughly characterized by FE-SEM, EDS, XRD, FT-IR, XPS and BET surface area techniques. The Fe doped materials were examined for adsorptive removal of lead (Pb2+) ions from aqueous solution. According to the adsorption screening experiments, the 5 wt% Fe doped GAC impregnated in ethanol and calcined under nitrogen demonstrated the highest removal of Pb2+ ions (86.6%). The adsorption results were found consistent with the surface and porous properties of the doped GAC. The 5 wt% Fe-GAC/ethanol/nitrogen illustrated the maximum surface area (715 m2/g), the largest pore diameter and volume, and the lowest size of Fe nanoparticles. The adsorption kinetics, isotherm and thermodynamics were evaluated for the remediation of Pb2+ ions by the optimized adsorbent. The kinetic analysis outcomes found well matched with the pseudo-second order model while the isotherm results modelling were well correlated with Redlich-Peterson, Sips and Langmuir models. The Langmuir highest adsorption capacity of Pb2+ ions was 124.3 mg/g at pH 4.7 and room temperature. The process of Pb2+ ions removal by Fe modified GAC was found as endothermic and spontaneous process as confirmed by the analysis of thermodynamic adsorption parameters. It was anticipated that both chemical and physical mechanisms were participated in the adsorption process including electrostatic interactions, complexation, ion exchange and surface adsorption.

Numerical simulation of a porous plate water sublimator working in the periodic mode and analytical study of its evaporation process

A water sublimator is a thermal control device that uses the phase change latent heat of water for heat rejection in space. It can allow effective heat dissipation in a microgravity environment. Existing models of water sublimators mainly focus on numerical simulations and do not calculate the temperature distribution and phase change interface position accurately. Furthermore, very few theoretical studies have been conducted. This study investigates a porous plate water sublimator, establishes the governing equations of each stage of a sublimator working in the periodic mode, and performs discrete calculations using the finite volume method. Additionally, a dimensionless analysis of the governing equations is conducted, and the flow in the evaporation process occurring in the porous plate is solved analytically. The results show that the sublimator enters a stable state after several periods. The effects of the thickness and pore diameter of the porous plate, feedwater pressure, and the type of working fluid on the evaporation process are discussed. It was observed that a large pore diameter and high feedwater pressure resulted in a rapid rise in the liquid level in the porous plate. An adaptive mesh method is used to induce a change in the length and number of meshes in accordance with the interface movement, thereby solving the problem caused by changes in the calculation domain. Moreover, an analytical solution of the evaporation process in the porous plate is provided, and it has universal significance for describing similar phenomena.

Graft Polymerization of Stearyl Methacrylate on PET Track-Etched Membranes for Oil-Water Separation.

In this article, results of PET track-etched membranes (PET TeMs) hydrophobized by photo-induced graft polymerization of stearyl methacrylate (SM) inside the pores were presented. The effects of monomer concentration, time of irradiation and the nature of the solvent on the degree of grafting and membrane morphology were investigated. The PET TeMs with pore diameters ranging from 350 nm (pore density of 1 × 108 pore/cm2) to 3.05 µm (pore density of 1 × 106 pore/cm2) were hydrophobized and tested for oil–water separation by using hexadecane–water and chloroform–water emulsions. Studies have shown high separation performance for membranes (up to 1100 mL/m2·s) with large pore diameters while achieving a high degree of purification.