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Superhydrophobic polyvinylidene fluoride (PVDF) membrane is a promising material for membrane distillation. Existing approaches for preparing superhydrophobic PVDF membrane often involve separate manipulation of surface roughness and surface chemistry. Here we report a one-step approach to simultaneously manipulate both the surface roughness and surface chemistry of PVDF nanofibrous membranes for enhanced direct-contact membrane distillation (DCMD) performances. The manipulation was realized in a unique solvent-thermal treatment process, during which a treatment solution containing alcohols was involved. We demonstrate that by using different chain-length alcohols in the treatment solvent, surface roughness can be promoted by creating nanofin structures on the PVDF nanofibers using an alcohol which has moderate affinity with PVDF. Meanwhile, surface chemistry can be tuned by adjusting the fraction distribution of crystal phases (nonpolar α phase and polar β phase) in the membrane using different alcohols. PVDF membranes with different surface wettabilities were used to evaluate the effects of surface roughness and surface energy on the DCMD performances. Combining both low surface energy and multi-scale surface roughness, pentanol-treated PVDF membrane achieved best anti-water property (water contact angle of 164.1° and sliding angle of 8.1°), and exhibited superior water flux and enhanced anti-wetting ability to low-surface-tension feed in the DCMD application.

To improve the pervaporation (PV) performance of isopropanol (IPA) dehydration, polyamide (PA) thin-film composite (TFC) membranes were fabricated by interfacial polymerization (IP) of 1,3-diaminopropane (DAPE) and trimesoyl chloride (TMC) on the surface of TiO2 modified ceramic hollow fiber (CHF) substrate. The TiO2 interlayer prepared by the sol-gel method completely cover the rough and macroporous surface of the α-Al2O3 hollow fiber, providing relatively smooth and intact surface but also abundant electrostatic sites (hydroxyl) for better IP. The PA layer prepared on the TiO2 interlayer is thinner, defect-free and exhibited higher smoothness and cross-linking degree than that on the original CHF support. The effects of monomer concentration, immersion time in aqueous phase and contact time of TMC solution were also investigated. The TFC membrane prepared under optimum conditions exhibited the outstanding PV separation index (PSI) value of 7.83 × 107 with separation factor above 12,000 and the permeate flux nearly 6.44 kg/m2 h for PV dehydration of 90 wt% IPA at 60 °C. After 100 h of long-term operation, the PV membrane maintains the high separation performance. This TFC membrane prepared by an effective and simple method provides an alternative for designing high-performance PV membrane in organics dehydration.

Thin film composite (TFC) polyamide membranes set the golden standard for reverse osmosis technology, but tuning their permeability and selectivity remains a major challenge because of the inherent permeability-selectivity trade-off. Creating nano-sized voids within the polyamide rejection layer can tune the membrane roughness and increase its effective filtration area to improve the water permeability. Here we prepare nano-foamed polyamide rejection layers by adding sodium bicarbonate into the aqueous solution of amine monomers. We show a systematic evolution of the roughness structure of polyamide membranes, with increasingly leaf-like and belt-like features appearing under enhanced nano-foaming conditions. These nano-foamed features can result in remarkable improvements in both water permeability and salt rejection and reduce membrane fouling propensity at the same time. Our study paves a new research direction for designing future generation of desalination membranes, which holds vast potential to reduce the cost and energy consumption of desalination while achieving improved product water quality.

Generating nanovoids/nanochannels in the polyamide rejection layer is an effective method to enhance the separation performance of thin-film composite (TFC) membranes. However, the excessive nanovoids/nanochannels formed in the rejection layer will cause defects and reduce the selectivity. Here we report a secondary interfacial polymerization (SIP) method to decorate the defects caused by one-dimensional (1D) nanochannels, which were generated by etching 1D copper hydroxide nanorods (CuNRs). The obtained SIP-1D NF membrane had a pure water permeability of 8.2 L·m-2·h-1 bar-1, while the divalent salts rejection was 92.0 ± 2.6% of Na2SO4, 91.3 ± 0.3% of MgCl2, and 91.8 ± 0.2% of MgSO4. Our work provides experimental basis for 1D nanochannels regulate the structures and properties of NF membrane.

In this study, sodium alginate (SA)-perfluorinated sulfonic acid (PFSA)/ceramic hybrid membranes were successfully prepared by dip-coating method. The contorted rigid structure of PFSA immobilized the loose structure of SA as well as improved the interconnectivity so as to demonstrated high separation factors. Meanwhile, the ion clusters formed by SO3H groups of PFSA possessed high affinity for water, resulting in high water flux. The viscosity of blend solution, structures and properties of the hybrid membranes were investigated by viscometry, Fourier transform infrared (FTIR), scanning electron microscopy (SEM), water contact angle meter and pervaporation dehydration. The effects of SA-PFSA ratio, PFSA content, feed composition and temperature on the separation performances of the hybrid membranes were investigated. The hybrid membrane fabricated by 2.0 wt% SA and 2.0 wt% PFSA demonstrated a high flux of 1155 g m−2 h−1 coupled with separation factor of 1149 by dehydration of 15 wt% water content ethanol-water mixture at 75 °C, reflecting superior pervaporation processing capacity.

Pervaporation (PV) is an effective approach for the removal of trace or micro substances from solutions. PV membrane is considered to be the most essential element for this process. In this study, the fabrication of ceramic hollow fiber PV membranes is demonstrated through multilayer assembly of poly(4-styrenesulfonic acid) and chitosan. The surface and cross-section morphologies, physical and chemical structures as well as the hydrophilicity of the membranes were characterized by field emission scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectrophotometer (FTIR) and water contact angle, respectively. The PV performance of the composite membranes was investigated by dehydration of water-ethanol solution. The effect of assembly solution concentration on PV performance was studied systematically. The assembled composite membranes with the concentration of 0.75 wt% PSS solution exhibited the highest PV separation index (PSI) value of 4.47 × 105 with flux of 495 g/m2 h and separation factor of 904 for dehydration of 10 wt% water-ethanol solution at 70 °C.

Due to environmental issues and intense competition in the marketplace, industries and governmental organizations invest in new technology research to improve productivity, environmental protection, and cost-efficiency. Pervaporation is a membrane-based separation technology, which is cost-effective, environmentally friendly, and efficient in the separation of azeotropic mixtures. Here, we report the fabrication of a hybrid membrane based on molybdenum disulfide (MoS2) material, which can be used to dehydrate alcohol through a pervaporation process. Ceramic hollow fiber (CHF) membrane was used as a substrate in MoS2hybrid membrane, and TiO2 intermediate layer was constructed to reduce the macropores on the CHF surface. Polyethyleneimine (PEI) was used as a binder in the fabrication of the MoS2 layer. MoS2-PEI layer was prepared by vacuum suction method and then crosslinked with trimesoyl chloride (TMC) to prevent the hybrid layer from swelling in an aqueous solution. We investigated the morphology and physicochemical characteristics of the hybrid membranes by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), atomic force microscopy (AFM), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and water contact angle (WCA) measurements. The fabricated MoS2hybrid membrane possesses a permeation flux of 5697 g m-2h−1 and separation factor of 320 in a 90 wt% isopropanol aqueous solution at 343 K. In this study, we provide a comprehensive understanding of the fabrication of MoS2hybrid membrane on the CHF membrane for efficient dehydration of isopropanol via the pervaporation process.

Perfluorinated sulfonic acid (PFSA)/polyether sulfone (PES) porous catalytic nanofiber was fabricated and applied to esterification reaction as catalyst in this work. To this aim, PES porous nanofibers were firstly prepared through electrospinning, and PFSA resin as catalyst was successfully anchored on these PES porous nanofibers through dip-coating method. Mesoporous structure was observed in PES porous nanofibers with high specific surface area of 40.6 m 2 /g. The catalytic properties of PFSA/PES porous catalytic nanofibers were measured by esterification of ethanol and acetic acid as model reaction. The recovery of PFSA/PES porous catalytic nanofibers remained 93.8% after three cycles of esterification, and the ion exchange capacity almost remained at a constant level, showing excellent recovery. For PFSA/PES porous catalytic nanofibers loaded with 5 wt% of PFSA as catalyst, the conversion rate and forward reaction kinetics constant achieved 85.8% at 1 h and 9.03 × 10 −4 m 3 kmol −1 s −1 g −1 , respectively.

The industrial applications of stainless steel single-channel hollow fiber (SCHF) membranes were confined by their restricted mechanical strength due to the small radial dimension. A stainless steel three-channel hollow fiber membrane (TCHF) was developed through the non-solvent induced phase separation (NIPS) method and then sintered in inert atmosphere. The combination of low mass transfer resistance of the SCHF membrane with high mechanical strength and large specific surface area of the new configuration enabled the TCHF membrane to overcome the weakness of mechanical strength without compromising other properties. The resultant TCHF sintered at 1100 °C showed a N2 permeation of 3.2×10−4 mol/(m2 s Pa) which was one order of magnitude higher than that of SCHF membrane and the fractural loading of 18.2N which was four times higher than that of SCHF membrane. The corrosion resistance tests proved the chemical stability in hostile fluids and the recycle performance confirmed the durability after tough cleaning several times. The rejection of starch wastewater was nearly 85% after a long-term operation, which showed the superior filtration performance. Therefore, stainless steel TCHF membrane exhibited great potentials in versatile applications such as microfiltration, gas separation, and catalytic reaction.

In this work, a novel hollow fiber catalytic packing (HFCP) was fabricated of ZrO 2 (shell)/TiO 2 (core) (TZ) solid superacid nanoparticles, perfluorinated sulfonic acid resin (PFSA) and polyethersulfone (PES) via wet-spinning method. TZ was a homemade binary solid superacid nanoparticles with core–shell structure using superfine titania (5 nm) as the core and mesoporous tetragonal phase zirconia as the shell. It was synthesized through the hydrolysis of zirconium oxychloride in the presence of titania nanoparticles and cetyltrimethylammonium bromide (CTAB) hexagonal crystals covered on the titania core and followed by calcination and acidification. HFCPs demonstrated well catalytic performance in the esterification test of ethanol and acetic acid due to the superacid sites on the surface of TZ and PFSA polymer chain. And the superacid sites on the PFSA polymer chain could be sufficiently exposed by the embedding of the nanoparticles. At the same time, HFCPs also showed ultrahigh recovery which was more than 99.5% in 6 runs because of the well integrality benefited from the wet-spinning method. The specific surface area (SSA) and pore size distribution were analyzed by N 2 adsorption–desorption, the result showed that the SSA of HFCPs decreased with the increasing of the PFSA additive amount. The SSA of the HFCP with the best catalytic performance could be up to 90.60 m 2 /g, in which the PFSA weight proportion was 13%. The XRD pattern and HRTEM image showed the HFCPs i.e. the zirconia shell of TZ formed uniform tetragonal phase. Other characterizations such as FT-IR, XPS, SEM and TEM were utilized to determine the chemical composition and morphology of the HFCPs and TZ, the results showed the novel catalytic packing was a suitable catalyst for the acid catalyzed reactions.

Thin-film composite (TFC) membranes as a promising candidate is also widely attracting many scholars' attention due to their ultrathin polyamide selective layers providing higher membrane flux at lower temperature for pervaporation. However, the generation of intact polyamide layer on large-porous support is facing significant hurdles. Here, a facile method using poly (4-styrenesulfonic acid) (PSS) as a scaffold was adopted to prepare directly TFC membranes on a ceramic support with a pore size of 0.97 μm. It was found that the TFC membranes with PSS scaffolds possess better adhesion between ceramic support and polyamide layer owing to the interaction of between sulfonic groups on PSS and hydroxyl groups on the porous support. The scanning electron microscopy (SEM) and water contact angle measurement were employed to characterize membrane morphologies and membrane hydrophilicity, respectively. The X-ray photoelectron spectrometer (XPS), Fourier transform infrared (FTIR) spectrometer and Super Conducting Fourier NMR Spectrometer were used to characterize and verify the chemical structures of the synthetic membranes. As a result, the TFC membranes were fabricated successfully on the ceramic support by the facile direct preparation method and they exhibit an excellent separation performance (e.g. membrane flux of 1.4 kg/m2h with separation factor of 1002 for 90 wt% ethanol dehydration) as compared to most reported membranes in the available literatures. Moreover, the developed TFC membranes exhibit a good stability, which indicates these novel TFC membranes possess great potential for pervaporation dehydration of organic solutions.

Thin-film composite (TFC) reverse osmosis (RO) membrane is the gold-standard for desalination and water reuse. Recent literature highlights the importance of polyamide (PA) rejection layer containing nanovoids to manipulate the water permeability and salt rejection. In this study, a facile template-assisted approach was applied to generate one-dimensional (1D) nanochannels in the polyamide rejection layer of RO membranes by preloading copper nanorods inside the PA layer followed by acid etching. In addition, a TFC RO membrane containing 0D nanovoids was also fabricated to compare the dimensional effect of nanochannels on membrane morphologies and performances. Specifically, the TFC-0D membrane only exhibited 61% higher water permeability compared to that of the control TFC, while the TFC-1D membrane showed 126% higher water flux with similar NaCl rejection, probably due to the dimensional improvement of the nanochannels inside the rejection layer. This templates-assisted approach paves a feasible way for fabricating high-performance next-generation RO membranes.

The development of thin-film nanocomposite (TFN) membranes for water treatment is of immense scientific interest. In this work, MoS2 nanosheets modified with tannic acid (TA)-Fe3+ coordination complexes were embedded within the polyamide (PA) layer to construct TFN nanofiltration (NF) membranes. The incorporation of modified MoS2 nanosheets into the PA matrix facilitates the formation of a bumpy surface with the appearance of scattered protuberances. Besides, the introduced covalent bonding between phenol groups and unreacted acid chloride groups during interfacial polymerization contributes to an enhanced crosslinking degree of the PA layer, simultaneously avoiding the formation of non-selective interfacial voids. The optimal TFN NF membrane with the addition of 0.01 wt% modified MoS2 nanosheets demonstrates 1.6-fold water permeance of the TFC membrane, along with increased salt rejection. The improved permeance of the TFN membrane is mainly due to the crumpled surface architecture with high roughness, which increases the permeable area for water transport. Overall, our study suggests that the employment of TA-MoS2 nanosheets for the construction of TFN membranes can be a promising method to develop high-performance NF membranes.

In this study, a novel positively charged nanofiltration (NF) membrane was fabricated by incorporating metal–organic frameworks (MOFs) into polyethyleneimine (PEI) and trimesic acid (TMA) cross-linking system. NH2-MIL-125(Ti) provides preferential water channels to improve the permeability of the composite membrane. The effects of NH2-MIL-125(Ti) loading on the membrane morphology, structure and properties were investigated by ATR-FTIR, SEM, EDS, AFM, Zeta potential measurements, etc. Studies have shown that the optimal preparation condition was determined at 0.010 wt% NH2-MIL-125(Ti) loading. The prepared membrane exhibited a high permeability of 12.2 L·m−2·h−1·bar−1 and a NiCl2 rejection of 90.9%. Compared with the pristine composite membrane, the membrane with appropriate amount of NH2-MIL-125(Ti) greatly improved the permeability (369.2%). The combination of NH2-MIL-125(Ti) and PEI/TMA cross-linking system has positive significance for the heavy metal wastewater treatment industry.

Zeolitic imidazolate framework-8 (ZIF-8) crystals with yolk-shell features were successfully synthesized through synergistic etching and surface functionalization method. The obtained yolk-shell ZIF-8 crystals (named as T-ZIF-8) presented excellent hydrophilicity and perfect dispersity in aqueous solution. Then polyamide thin-film nanocomposite (TFN) reverse osmosis (RO) membranes were fabricated by using the functionalized T-ZIF-8 as nanofillers. The obtained TFN RO membrane exhibited an improved surface hydrophilicity, an increased permeability of 1.1 L m−2 h−1 bar−1 (approximately 1.5 times) and a high rejection of 99.8% for NaCl aqueous solution. It has potential to resolve the trade-off problem between permeability and selectivity. Moreover, the obtained TFN RO membrane showed an excellent stability during a 25 h filtration test due to the enhanced compatibility between nanofillers and polyamide, which implied that the developed TFN RO membrane would have a great potential in desalination.

Fe3O4/Polyvinylidene fluoride (PVDF) three-channel hollow fiber catalytic membrane was successfully fabricated via non-solvent induced phase inversion and used for organic wastewater degradation in this work. The effects of Fe3O4 nanoparticles addition on the surface and cross-section morphologies, hydrophilicity and thermal properties of the catalytic membrane were characterized by the field emission scanning electron microscopy (SEM), water contact angle and thermogravimetric analysis (TGA), respectively. The obtained catalytic membrane exhibited good hydrophilicity, a high pure water flux of 175.8 L m−2 h−1 and a high removal of methylene blue (up to 97.6%) with Fenton catalytic reaction. Meanwhile, the catalytic membrane shows excellent anti-fouling property due to the presence of Fenton reaction. Our results show that Fe3O4/PVDF three-channel hollow fiber catalytic membrane was a promising alternative for the degradation of organic contaminants.

The Metal-organic frameworks (MOFs) have received extensive attention in membrane field due to their higher porosity, tunable structure and pores size. However, the weak hydrothermal or chemical stability limits their application in the separation of liquid mixtures. Here, a stable modified ZIF-8 (MZIF-8) as an interlayer of the composite membranes was designed using poly (4-styrenesulfonic acid) (PSS) to string together ZIF-8 nanoparticles. The membrane flux and separation factor increase with the increasing operation temperature, which echoes the higher active energy for permeation of water (EJ,W = 31.6 KJ/mol) than that of ethanol (EJ,E = 16.0 KJ/mol). Along with the decreasing ethanol feed concentration, the total flux increased from 0.81 kg/m2h to 4.47 kg/m2h while the separation factor decreased from 318 to 127. The selectivity of the polyamide/MZIF-8 (PA/MZIF-8) membranes for water-ethanol mixtures was found to be about five times higher than the ideal water-ethanol selectivity, demonstrating the ethanol permeance in membrane matrix was hindered by the preferential water adsorption of the PA/MZIF-8 membranes. The as-synthesized PA/MZIF-8 membranes not only exhibited excellent dehydrating performance for ethanol-water mixtures, but also operation stability under the higher temperature and acid conditions. Therefore, the PA/MZIF-8 membranes had great potential for industrial applications.

A facile fast surface crosslinking method was adopted to fabricate ceramic hollow fiber composite membranes with a thin separation layer for outstanding pervaporation (PV) performance. The morphologies, surface chemical compositions and hydrophilicity of the chitosan (CS)/ceramic hollow fiber composite membranes were characterized by field emission scanning electron microscopy (SEM), X-ray photoelectron analysis (XPS), and water contact angle (CA), respectively. The influences of CS concentration, feed composition and temperature on the membrane performances were investigated systematically. The operation time of the surface crosslinking process was several minutes (i.e., 4 min). The thickness of the separation layer of the obtained composite membranes ranged from 322 to 1414 nm, exhibiting excellent separation performance. The Arrhenius active energy (EJ and ED) and the diffusion coefficient (Dw and DIPA) were calculated to theoretically analyze the membrane separation process. The highest PV separation index (PSI) value was 8.2 × 106, indicating that the obtained membranes possessed enormous potential in IPA dehydration.

Molybdenum disulfide (MoS2), as a promising two-dimensional (2D) material, has become an alternative membrane material for desalination due to its molecular and ionic sieving properties. Here we report a construction of a positively charged MoS2 composite membrane on a ceramic hollow fiber (CHF). A TiO2 interlayer was prepared in advance to narrow the pore size and smoothen the surface of the CHF. Polyethyleneimine (PEI) was incorporated to enhance the interfacial adhesion between adjoining MoS2 sheets, as well as the MoS2 layer and the substrate, thus facilitating the formation of a tightly- and neatly-packed separation layer. Besides, PEI endowed the composite membrane with positively charged and hydrophilic surface. The structures and properties of these membranes were investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and water contact angle (WCA) measurement. The obtained MoS2/PEI composite membrane displayed an outstanding nanofiltration (NF) performance with superior stability. Our study provided an in-depth understanding for the fabrication of MoS2 composite membrane on the CHF for efficient water desalination.

We develop a novel polyvinylidene fluoride (PVDF) hollow fiber membrane utilizing the concept of in-situ self-assembly modulation, which is in terms of in-situ synthesis of amphiphilic copolymers and in-situ solubilization of polyvinylpyrrolidone (PVP). Utilizing the polytetrahydrofuran dimethacrylate ester (PTMGDA) and polyethylene glycol monomethyl ether methyl methacrylate (PEGMA) as reaction monomers, amphiphilic copolymers are in-situ synthesized, denoted as “P(PTMGDA-r-PEGMA)”. Results show that P(PTMGDA-r-PEGMA) and PVP have the synergistic effects on configuration and separation performance of PVDF membrane. P(PTMGDA-r-PEGMA) with high ratio in hydrocarbon chain (75.2%) and PVP not only effectively tunes micro-structure of the dope solutions but also results in the enhancement of the resultant membranes’ break strength and their stable permeability. Besides, the supramolecular aggregates of PVDF-P(PTMGDA-r-PEGMA)–PVP (size: 76–157 nm) work as “template” dependence of the macrovoids, which appear in the fibers׳ sponge-like cross-section structure, hence leading to the narrowing pore size distribution. Furthermore, the macrovoids’ size enlarges with the increase of content of P(PTMGDA-r-PEGMA) and PVP. It is also found that the permeation flux is controlled by the diffusion of PVP from the interior dope solution and pore-forming of P(PTMGDA-r-PEGMA) during demixing process, which is consistent with the in-situ self-assembly modulation concept. Finally, the newly developed PVDF hollow fiber membranes demonstrate remarkable long-term stable permeability.

In this study, a superhydrophobic nanofibrous membrane was prepared on the basis of an electrospun polyvinylidene fluoride (PVDF)–polytetrafluoroethylene (PTFE) nanofibrous scaffold coupled with a microporous PTFE substrate. The PVDF–PTFE nanofibrous scaffold was fabricated by electrospining of PVDF–PTFE blend solutions, it was observed that by changing the PTFE micro-powder content in the dope solutions from 0 wt.% to 12 wt.%, the water contact angle (WCA) and the liquid entry pressure (LEPw) of the membrane vary from 130.4° and 84 kPa to 152.2° and 137 kPa, respectively. The superhydrophobic PVDF–PTFE nanofibrous membrane was then tested for desalination by vacuum membrane distillation (VMD), a stable flux of 18.5 kg/m 2 h and salt rejection higher than 99.9% was presented throughout the entire testing period of 15 h, indicating the great potential of the PVDF–PTFE nanofibrous membranes in VMD. For further application of the PVDF–PTFE nanofibrous membranes in VMD, a mathematical model was presented to predict the vapor flux of the novel membrane under various operation conditions. A good agreement between the experimental and theoretical values for vapor fluxes was obtained; the results indicated that the VMD flux increased with the increase of feed temperature and flow rate and decreased with the increase of permeate pressure.

Difunctional hollow fiber ceramic composite membranes with self-sufficient catalysis and separation properties were successfully fabricated through thermal imidization, followed by dip-coating method. The structure, separation and catalysis properties of the fabricated difunctional membrane were investigated by SEM, pervaporation dehydration of methanol aqueous solution, and esterification of methanol and lauric acid to produce methyl laurate in a membrane reactor, respectively. The results showed that the obtained difunctional membrane was characterized by a multilayer structure: a sponge-like support layer, a dense separation layer and a porous catalysis layer. The porous catalysis layer had little effect on separation property. But it provided a large specific surface area for perfluorosulfonic acid (PFSA), resulting in a good catalytic effect. The obtained difunctional membrane also showed an excellent stability and repeatability. The optimized operating conditions were methanol to lauric acid ratio of 10:1, reaction temperature of 70 °C, and catalyst dosage of 1.0 wt% in this work. A mathematical model was established to describe this experimental process and the predicted results agreed well with the experimental results.

TiO2–SPPESK–PES nanocomposite membranes were successfully prepared using nano TiO2 to provide a high specific surface area, sulfonated poly(phthalazinone ether sulfone ketone) (SPPESK) with a 60% degree of sulfonation as a catalyst and polyether sulfone (PES) as a polymer support. The pore structure, morphology, water uptake, hydrophilic nature, degree of geometric swelling, mechanical properties and catalytic properties of the nanocomposite membranes were evaluated. A pseudo-homogeneous model was established to describe the kinetics of the esterification of acetic acid with ethanol. The results showed that TiO2–SPPESK–PES nanocomposite membranes had high specific surface areas (33.2–56.0 m2/g), mesopores structures (5–7 nm), good stability (swelling ratio less than 1.7% even at 80 °C), good mechanical strength and high catalytic activity (the conversion of ethanol reached to 82%), and good forward rate constants (6.28×10−3–13.6×10−3 L/(mol min)).

Using poly(vinyl alcohol) (PVA) as coating material, tartaric acid (Tac) and maleic anhydride (Mac) as cross-linking agents and the poly(acrylonitrile) (PAN) hollow fiber ultrafiltration membrane as support layer, the PVA/PAN composite membrane was prepared by dip-coating method used for pervaporation (PV) dehydration of ethyl acetate (EAc)/H 2 O solution. The PVA/PAN composite membrane was characterized by FT-IR spectra and SEM. The effects of cross-linking agents on the swelling degree and PV performance of PVA/PAN membrane were investigated, respectively. The separation factor of PVA/PAN composite membrane increased while the permeation flux decreased with increasing the contents of cross-linking agents, and PVA/PAN membrane exhibited better PV performance when Tac/PVA mass ratio was 0.2. Furthermore, the PV performance of PVA/PAN composite membrane for EAc/H 2 O solution was investigated with respect to the feed temperatures and feed water concentrations. For PVA/PAN composite membrane with Tac/PVA mass ratio of 0.2, its performance for 2 wt.% water of EAc solution at 40 °C was evaluated as follows: the separation factor and permeation flux were 7270 and 34.5 g m −2 h −1 , respectively. In addition, PVA/PAN composite membrane was also used for PV dehydration of EAc/ethanol (EtOH)/H 2 O ternary solution.

Based on the literature-reported compensatory effect of PI3K on Abl inhibition and the improved preclinical effect of drug combination of Abl and PI3K inhibitors, a series of compounds bearing novel scaffold of (S)-3-aminopyrrolidine was identified as Abl and PI3K dual inhibitors through support vector machine screening tool, which were subsequently synthesized and tested. Most compounds demonstrated promising cytoxicity against a CML leukemia cell-line K562 and moderate inhibition against Abl and PI3K kinases. These compounds induced no apoptosis in K562 cell-line, suggesting that their cytotoxic activities are unlikely duo to other known anti-CML mechanisms. Molecular docking study further showed that the compound 5k could bind with both Abl and PI3K, but the weaker binding with Abl compared to Imatinib is consistent with its low kinase inhibitory rates. These plus literature-reported evidences suggest that the promising cytotoxic effect of our novel compounds might be due to the collective effect of Abl and PI3K inhibition.

Perfluorosulfonic acid–poly(vinyl alcohol)–SiO 2 /poly(vinyl alcohol)/polyacrylonitrile (PFSA–PVA–SiO 2 /PVA/PAN) difunctional hollow fiber composite membranes (DHFCMs) with catalytic activity and selectivity have been prepared by dip-coating method. Both layers of DHFCMs were optimized independently. Firstly, separation-function hollow fiber composite membranes (SHFCMs) were prepared. The effects of different glutaraldehyde (GA) concentrations on SHFCMs and morphologies were investigated by FTIR and SEM. The separation performances of SHFCMs were measured by dehydrating the top product (water, ethanol and ethyl acetate ternary azeotropic system) of reactive distillation. Secondly, DHFCM was prepared by casting PFSA–PVA–SiO 2 catalytic solution on the top layer of SHFCM-4 with the best separation performance. The effects of different PFSA and nano-SiO 2 concentrations on DHFCMs, morphologies, element distribution, crystal structures and weight loss were investigated by FTIR, SEM, EDX, XRD and TGA. DHFCMs were evaluated by dehydrating the top product of reactive distillation and esterification reaction with acetic acid and ethanol. It was found that DHFCMs had better separation performances than single-separation-function HFCMs. DHFCMs with different PFSA and nano-SiO 2 concentrations manifested similar catalytic activity. DHFCM-1 had flux of 162 g/(m 2 h), separation factor of water to ethanol of 379, no ethyl acetate in the permeate. DHFCM made from DHCM-1 had the best separation performance and catalytic activity.

A support vector machine (SVM)-based virtual screening method is demonstrated as a rapid computational tool for the prediction of potential asymmetric organocatalysts for the direct aldol reaction. Our models show good accuracy at cross-validation and independent testing. Structure analyses of screening hits from the PubChem database revealed several new classes of compounds, including β-amino acids, diamines and hydrazides, as potential chiral organocatalysts.

Increasing antibiotic resistance has become a worldwide challenge to the clinical treatment of infectious diseases. The identification of antibiotic resistance proteins (ARPs) would be helpful in the discovery of new therapeutic targets and the design of novel drugs to control the potential spread of antibiotic resistance. In this work, a support vector machine (SVM)-based ARP prediction system was developed using 1308 ARPs and 15587 non-ARPs. Its performance was evaluated using 313 ARPs and 7156 non-ARPs. The computed prediction accuracy was 88.5% for ARPs and 99.2% for non-ARPs. A potential application of this method is the identification of ARPs non-homologous to proteins of known function. Further genome screening found that ca. 3.5% and 3.2% of proteins in Escherichia coli and Staphylococcus aureus, respectively, are potential ARPs. These results suggest the usefulness of SVMs for facilitating the identification of ARPs. The software can be accessed at SARPI (Server for Antibiotic Resistance Protein Identification).

Support vector machines (SVM) and other machine-learning (ML) methods have been explored as ligand-based virtual screening (VS) tools for facilitating lead discovery. While exhibiting good hit selection performance, in screening large compound libraries, these methods tend to produce lower hit-rate than those of the best performing VS tools, partly because their training-sets contain limited spectrum of inactive compounds. We tested whether the performance of SVM can be improved by using training-sets of diverse inactive compounds. In retrospective database screening of active compounds of single mechanism (HIV protease inhibitors, DHFR inhibitors, dopamine antagonists) and multiple mechanisms (CNS active agents) from large libraries of 2.986 million compounds, the yields, hit-rates, and enrichment factors of our SVM models are 52.4–78.0%, 4.7–73.8%, and 214–10,543, respectively, compared to those of 62–95%, 0.65–35%, and 20–1200 by structure-based VS and 55–81%, 0.2–0.7%, and 110–795 by other ligand-based VS tools in screening libraries of ≥1 million compounds. The hit-rates are comparable and the enrichment factors are substantially better than the best results of other VS tools. 24.3–87.6% of the predicted hits are outside the known hit families. SVM appears to be potentially useful for facilitating lead discovery in VS of large compound libraries.

Identification and validation of viable targets is an important first step in drug discovery and new methods, and integrated approaches are continuously explored to improve the discovery rate and exploration of new drug targets. An in silico machine learning method, support vector machines, has been explored as a new method for predicting druggable proteins from amino acid sequence independent of sequence similarity, thereby facilitating the prediction of druggable proteins that exhibit no or low homology to known targets.

Polymer gel electrolyte with addition of fumed silica was prepared by the UV polymerization of methyl methacrylate, oligomer of ethyl glycol dimethacrylate and liquid electrolyte. The effect of fumed silica on the interfacial stability of lithium electrode and polymer gel electrolyte membrane was studied by environmental scanning electron microscopy (ESEM), FTIR and electrochemical AC impedance. The addition of fumed silica has an effect on morphology of polymer gel electrolyte membrane. The silica is interactive with solvent and polymer matrix and it can trap impurities in the polymer gel electrolyte. All of them are beneficial to the interfacial stability, which is confirmed in the AC impedance spectrum.

SnO2/multi-walled carbon nanotube (MWCNT) composite was prepared via a diffusion method. Firstly the MWCNT was sonicated in a filtrate which was derived from a tin dichloride solution mixed with AgNO3 solution. Then the SnO2/MWCNT composite was prepared whereby, after calcination in N2 atmosphere, the salts inside the MWCNT decomposed to SnO2. The resulting composite was characterized by transmission electron microscopy, Raman spectroscopy and X-ray diffraction, which indicated that SnO2 had infiltrated into the MWCNT and filled the interior. The subsequent evaluation of the electrochemical performance in lithium ion batteries showed that the SnO2/MWCNT composite had a reversible discharge capacity of 505.9 mAh∙g− 1 after 40 cycles, as compared to 126.4 mAh∙g− 1 for pure nano-SnO2.