Synthesis of Hierarchically Supported TS-2 Zeolites and Catalytic Application in the Epoxidation of Allyl Chloride.

Construction of hierarchical pore structure in supported titanium silicalites was an effective strategy to enhance catalytic performance and avoid the separation process in industrial applications. Herein, the hierarchical TS-2 zeolites were successfully prepared on the TiO-modified α-AlO pellets by "bottom-up" method, which had good and stable catalytic performance for the allyl chloride epoxidation. TritonX-100 could construct a mesopore structure, restrain nucleation, and affect titanium coordination of the zeolites, which was beneficial for preparing large size, much hexa-coordination titanium content, and hierarchically supported TS-2 zeolites in this work.

Preparation and Modification of Silicalite-2 Membranes.

Silicalite-2 membranes were successfully prepared on tubular α-AlO supports by secondary hydrothermal synthesis, and the pervaporation performance of the membrane was evaluated by separation of a 5 wt% ethanol/HO mixture at 60 °C. The effects of templating agent content, water-silicon ratio and crystallization time on the separation performance of Silicalite-2 membranes were investigated. When the TBAOH/SiO and HO/SiO molar ratios of the precursor synthesis solution were 0.

Electrospun nanofibers applications in caries lesions: prevention, treatment and regeneration.

Dental caries is a multifactorial disease primarily mediated by biofilm formation, resulting in a net loss of mineral content and degradation of organic matrix in dental hard tissues. Caries lesions of varying depths can result in demineralization of the superficial enamel, the formation of deep cavities extending into the dentin, and even pulp infection. Electrospun nanofibers (ESNs) exhibit an expansive specific surface area and a porous structure, closely mimicking the unique architecture of the natural extracellular matrix (ECM).

Fabrication and enhanced visible-light photocatalytic Hproduction of B-doped N-deficient g-CN/CdS Hybrids with robust 2D/2D hetero-interface interaction.

2D layered photocatalysts with proper electronic structure have sparked much attention in the field of visible-light photocatalysis for Hproduction. Herein, by simply calcining the mixture of ultrathin g-CN(CNN) and NaBH, heteroatom B and N defect were simultaneously introduced into g-CN. The obtained modified g-CN(BDCNN) was further coupled with 2D flower-like CdS nanosheet.

Improved Esterification of Citric Acid and n-Butanol Using a Dense and Acid-Resistant Beta Zeolite Membrane.

In this work, a dense and acid-resistant beta zeolite membrane was applied to improve the esterification of citric acid and n-butanol, for the first time. Through the continuous removal of the by-product water via pervaporation (PV), the conversion of citric acid was significantly enhanced from 71.7% to 99.

A novel amelogenesis-inspired hydrogel composite for the remineralization of enamel non-cavitated lesions.

Enamel non-cavitated lesions (NCLs) are subsurface enamel porosity from carious demineralization. The developed enamel cannot repair itself once NCLs occurs. The regeneration of mineral crystals in a biomimetic environment is an effective way to repair enamel subsurface defects.

Hierarchical S-Scheme Heterostructure of CdInS@UiO-66-NH toward Synchronously Boosting Photocatalytic Removal of Cr(VI) and Tetracycline.

Developing highly efficient photocatalysts toward synchronously removing heavy metals and organic pollutants is still a serious challenge. Herein, we depict hierarchical S-scheme heterostructured photocatalysts prepared via in situ anchoring UiO-66-NH nanoparticles onto the CdInS porous microsphere structures assembled with numerous nanosheets. In the mixed system of Cr(VI) and tetracycline (TC), the optimal photocatalyst (CIS@U66N-30) shows remarkable photocatalytic activities toward the synchronous removal of Cr(VI) (97.

self-assembly fabrication of ultrathin sheet-like CuS modified g-CNheterojunction and its enhanced visible-light photocatalytic performance.

Photocatalysts with heterojunction structure have been widely used for organic degradation. In this study, CuS/g-CNheterojunction was formed byself-assembly via a simply hydrothermal method. A series of characterizations were applied to analyzing the morphology, structure, optical properties and photo-induced electron transfer of the samples.

Preparation of Pebax 1657/MAF-7 Mixed Matrix Membranes with Enhanced CO/N Separation by Active Site of Triazole Ligand.

Fillers play a critical role in the performance of mixed matrix membranes (MMMs). Microporous metal azolate frameworks (MAFs) are a subclass material of metal-organic frameworks (MOFs). Due to the uncoordinated nitrogen of the organic ligands, MAF-7 (SOD-[Zn(mtz)], Hmtz = 3-methyl-1,2,4-triazole, window: d = 0.

Nitrogen-rich triazine-based porous polymers for efficient removal of bisphenol micropollutants.

Achieving both rapid adsorption rate and high adsorption capacity for bisphenol micropollutants from aquatic systems is critical for efficient adsorbents in water remediation. Here, we elaborately prepared three nitrogen-rich triazine-based porous polymers (NTPs) with similar geometric configurations and nitrogen contents (41.70-44.

Enhanced Hevolution performance by carbonized SiC/g-CNheterojunction under visible-light illumination.

In this study, carbonized silicon carbide/graphitic carbon nitride ((SiC/C)/g-CN) composites were fabricated via a facile calcination method. The optimal SiC/C/g-CNcomposite shows an excellent visible-light photocatalytic activity for water splitting, with the highest hydrogen evolution amount being 200.2mol, which is four times higher than that of pure g-CNwhen triethanolamine and platinum (1.

Template Removal and Surface Modification of an SSZ-13 Membrane with Heated Sodium Chloride for CO/CH Gas Separation.

Hydrothermal synthesis with an organic template of ,, trimethyl-1-adamantammonium hydroxide (TMAdaOH) is the most commonly used method to prepare an SSZ-13 zeolite membrane. In this paper, the synthesized membrane was treated in heated sodium chloride to remove TMAdaOH instead of calcination in air. The surface of the membrane was modified by the heated NaCl and resulted in an improved CO/CH gas separation selectivity.

The pH-Responsive Property of Antimicrobial Peptide GH12 Enhances Its Anticaries Effects at Acidic pH.

Dental caries is closely related to the acidification of the biofilms on the tooth surface, in which cariogenic bacteria bring about a dramatic pH decrease and disrupt remineralisation equilibrium upon the fermentation of dietary sugars. Thus, approaches targeting the acidified niches with enhanced anticaries activities at acidic pH are highly desirable. In our previous study, a cationic amphipathic α-helical antimicrobial peptide GH12 (Gly-Leu-Leu-Trp-His-Leu-Leu-His-His-Leu-Leu-His-NH2) was designed with good stability, low cytotoxicity, and excellent antibacterial effects.

Different Hydrogen Bond Changes Driven by Surface Segregation Behavior of Imidazolium-Based Ionic Liquid Mixture at the Liquid-Vacuum Interface.

In this work, molecular dynamics (MD) simulations were carried out to study the behaviors of a binary ionic liquid (IL) mixture consisting of equimolar [CCIm][BF] and [CCIm][BF], as well as two corresponding pure ILs, at the liquid-vacuum interface. Our simulation results show that the competition of nonpolar interactions between different alkyl chains of two cations results in an obvious surface segregation behavior of the IL mixture at the interface, indicating an enhanced aggregation of the [CCIm] cations but a weakened aggregation of the [CCIm] cations at the outermost surface. More interestingly, different hydrogen bond (HB) changes between two imidazolium cations at the interface can be driven by such surface segregation behavior, where the [CCIm] cations rather than the [CCIm] ones have more and stronger HBs with the [BF] anions by comparison with the corresponding pure ILs at the interface.

Molecular-level insights into the structures, dynamics, and hydrogen bonds of ethylammonium nitrate protic ionic liquid at the liquid-vacuum interface.

A series of molecular dynamics simulations have been used to systematically explore the structures, dynamics and hydrogen bonds (HBs) of ethylammonium nitrate (EAN) protic ionic liquid (IL) and their mutual relationship at the liquid-vacuum interface. The simulation results clearly demonstrate that there exists a sandwich structure at the interface, with the double-layer of the EA+ cations on both sides and one intercalated layer of the NO3- anions in the middle. Wherein, the outermost cation layer prefers the orientation with the CH3 groups pointing to the vacuum phase due to the hydrophobic interactions, while the CH3 groups in the second layer direct to the bulk liquid phase owing to the HB formation between their NH3+ groups and the intercalated NO3- anions in the middle layer.

Antimicrobial Peptide GH12 Prevents Dental Caries by Regulating Dental Plaque Microbiota.

Due to the complex microecology and microenvironment of dental plaque, novel caries prevention strategies require modulating the microbial communities ecologically and reducing the cariogenic properties effectively. Antimicrobial peptide GH12 reduced the lactic acid production and exopolysaccharide (EPS) synthesis of a biofilm and a three-species biofilm in previous studies. However, the anticaries effects and microecological effects of GH12 remained to be investigated in a complex biofilm model and an animal caries model In the present study, GH12 at 64 mg/liter showed the most effective inhibition of lactic acid production, EPS synthesis, pH decline, and biofilm integrity of human dental plaque-derived multispecies biofilms , and GH12 at 64 mg/liter was therefore chosen for use in subsequent and assays.

Separation Selectivity of CH/CO Gas Mixtures in the ZIF-8 Membrane Explored by Dynamic Monte Carlo Simulations.

Here we report a series of nonequilibrium dynamic Monte Carlo simulations combined with dual control volume (DCV-DMC) to explore the separation selectivity of CH/CO gas mixtures in the ZIF-8 membrane with a thickness of up to about 20 nm. Meanwhile, an improved DCV-DMC approach coupled with the corresponding potential map (PM-DCV-DMC) is further developed to speed up the computational efficiency of conventional DCV-DMC simulations. Our simulation results provide the molecular-level density and selectivity profiles along the permeation direction of both CH and CO molecules in the ZIF-8 membrane, indicating that the parts near membrane surfaces at both ends play a key role in determining the separation selectivity.

Effects of Seed Crystals on the Growth and Catalytic Performance of TS-1 Zeolite Membranes.

Dense and good catalytic performance TS-1 zeolite membranes were rapidly prepared on porous mullite support by secondary hydrothermal synthesis. The properties of seed crystals were very important for the preparation of high-catalytic performance TS-1 zeolite membranes. Influences of seed crystals (Ti/Si ratios, size, morphology, and zeolites concentration of the seed suspension) on the growth and catalytic property of TS-1 zeolite membranes were investigated in details.

Enhanced Visible-Light Photocatalytic Performance of SAPO-5-Based g-CN Composite for Rhodamine B (RhB) Degradation.

Novel visible-light responded aluminosilicophosphate-5 (SAPO-5)/g-CN composite has been easily constructed by thermal polymerization for the mixture of SAPO-5, NHCl, and dicyandiamide. The photocatalytic activity of SAPO-5/g-CN is evaluated by degrading RhB (30 mg/L) under visible light illumination (λ > 420 nm). The effects of SAPO-5 incorporation proportion and initial RhB concentration on the photocatalytic performance have been discussed in detail.

Transcatheter arterial embolization for postoperative arterial complications after pelvic or hip surgery.

Purpose: We aimed to study the technical and clinical outcome of urgent transcatheter arterial embolization (TAE) for postoperative arterial complications after pelvic or hip surgery, and to accumulate additional experience about the role of embolization for these injuries.

Methods: Patients who received TAE procedure for arterial complications after pelvic or hip surgery between September 1st, 2002 and December 1st, 2014 were screened on medical records and included in the analysis. Angiographic findings included active contrast agent extravasation, pseudoaneurysm formation, arteriovenous fistula, and other suspicious signs such as sighting of coarse margin or distortion of vessels.

Single Gas Permeance Performance of High Silica SSZ-13 Zeolite Membranes.

Continuous and high silica SSZ-13 zeolite membranes were prepared on porous mullite supports from high SiO₂/Al₂O₃ ratio or aluminum-free precursor synthesis gel. Single gas permeance (CO₂ and CH₄) of the high silica SSZ-13 zeolite membrane was decreased with the SiO₂/Al₂O₃ ratio in the precursor synthesis gel, while the ideal CO₂/CH₄ selectivity of the membrane was gradually increased. Moreover, effects of synthesis conditions (such as H₂O/SiO₂ and RNOH/SiO₂ ratios of precursor synthesis gel, crystallization time) on the single gas permeance performance of high silica SSZ-13 zeolite membranes were studied in detail.

Unique orientations and rotational dynamics of a 1-butyl-3-methyl-imidazolium hexafluorophosphate ionic liquid at the gas-liquid interface: the effects of the hydrogen bond and hydrophobic interactions.

Here we report a series of molecular dynamics simulations for the orientations and rotational dynamics of the 1-butyl-3-methyl-imidazoliumhexafluorophosphate ([BMIM][PF]) ionic liquid (IL) at the gas-liquid interface. Compared to the bulk phase, the [BMIM] cations at the interface prefer to orientate themselves with their imidazolium rings perpendicular to the gas-IL interface plane and their butyl chains pointing toward the vacuum phase. Such a preferential orientation can be attributed to the combined effect of the hydrophobic interactions and the optimum loss of hydrogen bonds (HBs).

Controlled Synthesis of MOF-Encapsulated NiPt Nanoparticles toward Efficient and Complete Hydrogen Evolution from Hydrazine Borane and Hydrazine.

The catalytic dehydrogenation of hydrazine borane (NHBH) and hydrous hydrazine (NH·HO) for H evolution is considered as two of the pivotal reactions for the implementation of the hydrogen-based economy. A reduction rate controlled strategy is successfully applied for the encapsulating of uniform tiny NiPt alloy nanoclusters within the opening porous channels of MOFs in this work. The resultant NiPt/MOF core-shell composite with a low Pt content exerted exceedingly high activity and durability for complete H evolution (100% hydrogen selectivity) from alkaline NHBH and NH·HO solution.

Molecular Dynamics Simulations for Loading-Dependent Diffusion of CO, SO, CH, and Their Binary Mixtures in ZIF-10: The Role of Hydrogen Bond.

The loading-dependent diffusion behavior of CH, CO, SO, and their binary mixtures in ZIF-10 has been investigated in detail by using classical molecular dynamics simulations. Our simulation results demonstrate that the self-diffusion coefficient D of CH molecules decreases sharply and monotonically with the loading while those of both CO and SO molecules initially display a slight increase at low uptakes and follow a slow decrease at high uptakes. Accordingly, the interaction energies between CH molecules and ZIF-10 remain nearly constant regardless of the loading due to the absence of hydrogen bonds (HBs), while the interaction energies between CO (or SO) and ZIF-10 decease rapidly with the loading, especially at small amounts of gas molecules.