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Bimetallic atom catalysts exhibit ultra-high oxygen electrocatalytic activity by harnessing mutual promotion and synergistic effects between adjacent metal active centers, surpassing the performance of single metal atomic catalysts. Herein, FeNi atom pairs protected by hierarchical porous annular carbon grids (P-FeNi-NPC) are introduced using a mediator-assisted MOFs-derived strategy. The introduction of the multi-block copolymer P123 ensures the uniform confinement and dispersion of metal ions, followed by thermal decomposition to form a "planetary-ring-like" carbon framework that anchors the bimetallic atomic pairs in the active region. The homogeneous distribution of adjacent Fe-N 4 and Ni-N 4 active sites significantly enhances catalytic activity and stability. Leveraging unique electronic and geometric structures, the resulting P-FeNi-NPC catalyst demonstrates exceptional ORR and OER activities with an ΔE value of 0.705 (E 1/2 = 0.845 V, E j = 10 = 1.55 V). Theoretical calculations unveil that FeNi bimetallic sites loaded on nitrogen-doped carbon frameworks with specific curvature effectively modulate the energy of d-band centers, thus balancing the free energy of oxygen-containing intermediates. This study presents a novel and versatile approach for synthesizing advanced bifunctional catalysts, poised to drive the future development of Zn-air batteries., (© 2024 Wiley‐VCH GmbH.)

The purpose of this study is to prepare monodisperse silica mesoporous microspheres with narrow pore size distribution to promote their application in the field of liquid chromatography. An improved emulsion method was used to prepare silica mesoporous microspheres, and the rotary evaporation temperature, emulsification speed, dosage of porogen DMF, and dosage of the catalyst NH 3 ·H 2 O were optimized. Subsequently, these microspheres were respectively treated by alkali-heating, calcination, and sieving. The D 50 (particle size at the cumulative particle size distribution percentage of 50%) of as-prepared silica mesoporous microspheres is 26.3 μm, and the D 90 /D 10 (the ratio of particle size at a cumulative particle size distribution percentage of 90% to a cumulative particle size distribution percentage of 10%) is 1.94. The resultant silica mesoporous microspheres have distinctive pore structures, with a pore volume of more than 1.0 cm 3 /g, an average pore size of 11.35 nm, and a median pore size of 13.4 nm. The silica mesoporous microspheres with a large particle size, uniform particle size distribution, large average pore size and pore volume, and narrow mesopore size distribution can basically meet the requirements of preparative liquid chromatographic columns.

Silicon carbide (SiC) ceramics with high bending strength were prepared by hot pressing sintering (HPS) with yttrium aluminum garnet (Y 3 Al 5 O 12 , YAG) as sintering additive, and the effects of YAG content and sintering temperature on the sintering behavior, microstructure and mechanical properties of SiC ceramics were investigated in detail. The uniform distribution of YAG to form a liquid phase and the driving force provided by hot pressing sintering decrease the sintering temperature, improve the densification of SiC ceramics, and refine the crystal size. By means of suitable sintering conditions with the additional amount of YAG of 5 wt%, the sintering temperature of 1950 °C and a pressure of 30 MPa, the resultant SiC/YAG composite ceramics possesses high sintering and mechanical properties with the relative density of 98.53%, the bending strength of 675 MPa, the Vickers hardness of up to 17.92 GPa, and the elastic modulus of 386 GPa. The as-prepared SiC/YAG composite ceramics are promisingly used as the dry gas seal materials in the centrifugal compressors.

The aim of this study is to reduce the manufacturing cost of a hydrophobic and heat-insulating silica aerogel and promote its industrial application in the field of thermal insulation. Silica aerogels with hydrophobicity and thermal-insulation capabilities were synthesized by using water-glass as the silicon source and supercritical drying. The effectiveness of acid and alkali catalysis is compared in the formation of the sol. The introduction of sodium methyl silicate for the copolymerization enhances the hydrophobicity of the aerogel. The resultant silica aerogel has high hydrophobicity and a mesoporous structure with a pore volume exceeding 4.0 cm 3 ·g -1 and a specific surface area exceeding 950 m 2 ·g -1 . The obtained silica aerogel/fiber-glass-mat composite has high thermal insulation, with a thermal conductivity of less than 0.020 W·m -1 ·K -1 . The cost-effective process is promising for applications in the industrial preparation of silica aerogel thermal-insulating material.

Energy storage via anionic redox provides extra capacity for lithium-rich manganese-based oxide cathodes at high voltage but causes gradual structural collapse and irreversible capacity loss with generation of O n - (0 ≤ n < 2) species upon deep oxidation. Herein, the stability and reversibility of anionic redox reactions are enhanced by a simple sulfur-assisted surface modification method, which not only modulates the material's energy band allowing feasible electron release from both bonding and antibonding bands, but also traps the escaping O n - via an as-constructed SnS 2- x - σ O y coating layer and return them to the host lattice upon discharge. The regulation of anionic redox inhibits the irreversible structural transformation and parasitic reactions, maintaining the specific capacity retention of as-modified cathode up to 94% after 200 cycles at 100 mA g -1 , along with outstanding voltage stability. The reported strategy incorporating energy band modulation and oxygen trapping is promising for the design and advancement of other cathodes storing energy through anion redox., (© 2023 Wiley-VCH GmbH.)

Lithium-sulfur (Li-S) batteries are considered as one of the top competitors to go beyond Li-ion batteries. However, the shuttle effect triggered by soluble lithium polysulfides (LPSs) brings great troubles for understanding the solid-liquid-solid conversion process of the sulfur cathode. Herein, a new characterization technique is developed to deepen the understanding of such soluble LPSs shuttling, by integrating an electron-conductive interlayer. The voltage of the interlayer exhibits a voltage-adaptive effect to the cathode, indicating the true dependence of the open-circuit voltages on the LPSs instead of on the solid cathodes. Furthermore, a quantitative method can be introduced to monitor the shuttling LPSs by such interlayer design, and it shows great potential to be a new standard technique, providing direct comparison of the shuttle effect between different studies. The newly developed interlayer design paves an avenue to gain new insight into the reaction process and improve the performance of Li-S batteries., (© 2023 Wiley-VCH GmbH.)

Transition metal sulphide electrocatalytic materials possess the bright overall water-splitting performance of practical electrocatalytic technologies. In this study, an amethyst-like MoS 2 @Ni 9 S 8 /Co 3 S 4 rod electrocatalyst was constructed via a one-step hydrothermal method with in-situ-grown ZIF-67 nanoparticles on nickel foam (NF) as a precursor. The rational design and synthesis of MoS 2 @Ni 9 S 8 /Co 3 S 4 endow the catalyst with neat nanorods morphology and high conductivity. The MoS 2 @Ni 9 S 8 /Co 3 S 4 /NF with the amethyst-like rod structure exposes abundant active sites and displays fast electron-transfer capability. The resultant MoS 2 @Ni 9 S 8 /Co 3 S 4 /NF exhibits outstanding hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) electrocatalytic activities, with low overpotentials of 81.24 mV (HER) at 10 mA cm -2 and 159.67 mV (OER) at 50 mA cm -2 in 1.0 M KOH solution. The full-cell voltage of overall water splitting only achieves 1.45 V at 10 mA cm -2 . The successful preparation of the amethyst-like MoS 2 @Ni 9 S 8 /Co 3 S 4 rod electrocatalyst provides a reliable reference for obtaining efficient electrocatalysts for overall water splitting.

Cellulose aerogels are the latest generation of aerogels and have also received extensive attention due to their renewable and biocompatible properties. Herein, cellulose aerogel was facilely prepared by using NaOH/urea solution as solvent, raising the temperature to control gelation and drying wet gel sequentially. With NaOH/urea solution as solvent, the cellulose concentration has an important impact on the micromorphology of cellulose aerogels, while the aging time rarely affects the micromorphology. The appropriate solvent and drying method allow the formation of different cellulose crystalline structures. Different from the Cellulose Ⅰ crystalline structure of raw cellulose powder, the cellulose phase of as-prepared cellulose aerogels belongs to the Cellulose Ⅱ crystalline structure, and to some extent the pyrolysis temperature is also lower than that of raw cellulose powder. The resultant cellulose aerogel prepared by using NaOH/urea solution as solvent and freeze-drying has a uniform macroporous structure with a macropore size of 1~3 µm.

Increasing the energy density of lithium-ion batteries (LIBs) can broaden their applications in energy storage but remains a formidable challenge. Herein, with polyacrylic acid (PAA) as phase separation agent, macroporous Co 2 SnO 4 with hollow skeletons was prepared by sol-gel method combined with phase separation. As the anode of LIBs, the macroporous Co 2 SnO 4 demonstrates high capacity retention (115.5% at 200 mA·g -1 after 300 cycles), affording an ultrahigh specific capacity (921.8 mA h·g -1 at 1 A·g -1 ). The present contribution provides insight into engineering porous tin-based materials for energy storage.

High-efficiency, good electrical conductivity and excellent performance electrocatalysts are attracting growing attention in the field of overall water splitting. In order to achieve the desirable qualities, rational construction of the structure and chemical composition of electrocatalysts is of fundamental importance. Herein, petal-like structure Ni 0.33 Co 0.67 P shells grown on conductive silver nanowires (Ag NWs) cores as bifunctional electrocatalysts for overall water splitting were synthesized through a facile hydrothermal method and phosphorization. The resultant three-dimensional core-shell petal-like structure Ag NWs@Ni 0.33 Co 0.67 P possesses excellent catalytic activities in alkaline conditions with the overpotential of 259 mV for the oxygen evolution reaction (OER), 121 mV for the hydrogen evolution reaction (HER) and a full cell voltage of 1.64 V to reach the current density of 10 mA cm -2 . Highly conductive Ag NWs as cores and high surface area petal-like Ni 0.33 Co 0.67 P as shells can endow outstanding catalytic performance for the bifunctional electrocatalyst. Thus, the synthetic strategy of the three-dimensional core-shell structure Ag NWs@Ni 0.33 Co 0.67 P considerably advances the practice of Ag NWs toward electrocatalysts.

Highly flexible silver nanowire-based transparent conductive films (AgNWs TCFs) were large-scale fabricated by slot-die coating AgNWs inks on a flexible polyethylene terephthalate (PET) substrate, and further fabricated into a transparent film heater. Appropriate flow rate, coating speed, and AgNWs concentration allow the construction of the 15 cm × 15 cm AgNW TCFs with a sheet resistance ( R s ) of less than 20 Ω/sq, a transmittance ( T ) at 550 nm higher than 95%, and a haze less than 3.5%. The resultant AgNW TCFs heater possesses high uniformity and superior mechanical stability and can reach a Joule heating temperature of 104 °C with a voltage of 12 V. The slot-die coating method has great potential for large-scale production of AgNW based film heaters promisingly used in window defrost and deicer systems.

Microwave heating technology is known as an alternative to traditional gas and electric heating sources. In this work, mesoporous methylsilsesquioxane (MSQ) aerogels were prepared via a sol-gel process accompanied by microwave heating technology, and microwave heating was used in the gelation of sol and the drying of wet gels, respectively. The effects of hexadecyltrimethylammonium chloride (CTAC) as a surfactant and template, hydrochloric acid (HCl) as a catalyst, ethanol as a solvent, sodium hydroxide (NaOH) as a gelation agent, and microwave power on the pore structure of as-prepared MSQ aerogels were investigated in detail. Microwave heating at low power results in the acceleration of sol-gel transition and achieves the gelation within a few minutes. Appropriate amounts of chemical reagents and microwave heating at high power allow the preparation of mesoporous MSQ aerogels with a BET-specific surface area of 681.6 m 2 ·g -1 and a mesopore size of 19 nm, and the resultant MSQ aerogel still has a BET specific surface area as high as 134 m 2 ·g -1 after heat treatment at 600 °C for 2 h, showing high thermal stability. The MSQ aerogels/fibre composite possesses a low thermal conductivity of 0.039 W/(m·k) -1 , displaying good thermal insulation. Microwave heating technology is a promising heating method for the preparation of other aerogels.

Hierarchically porous carbon aerogels (CAs) were prepared by organic condensation gelation method combined with atmospheric drying and pore-formation technology, followed by a carbonization process. With as-prepared CAs as substrate, the transition metal oxide nanoparticles loaded CAs composites (MnO 2 /Mn 2 O 3 @CA and Ni/NiO@CA) were achieved by means of liquid etching method combined with heat treatment, respectively. The catalyst, pore-forming agent and etching have important roles on the apparent density and pore structure of CAs. The hydrochloric acid (catalyst) significantly accelerates the gelation process and influences the size and distribution of macropores, whereas the addition of PEG2000 (pore-forming agent) and the etching of liquid solution leads to the formation of mesopore structure in CAs. Appropriate amounts of hydrochloric acid and PEG2000 allow the formation of hierarchically porous CAs with a BET surface area of 482.9 m 2 ·g -1 and a macropore size of 11.3 μm. After etching and loading, the framework of CAs is etched to become a mesoporous structure, and the transition metal oxide nanoparticles can be uniformly loaded in CAs. These resultant composites have promising application in super capacitor, electrocatalysis, batteries and other fields.

This paper focuses on the light transmittance of macroporous silica as a photocatalyst carrier. In addition to the characteristics of photocatalysts, the structure of porous bulk is also important since it affects the propagation of light. Realistic porous structures are generated by a Voronoi-based approach. Four morphological parameters are highly controlled during generating, that is, porosity, coefficient of variation, diameter ratio and normalized curvature. Finite element method (FEM) is used to simulate the propagation of light in the porous models in the visible light range. The intensity shows a quadratic decrease with the increase of the depth of light propagation. The influences of the morphological parameters on the light transmittance are analysed. It turns out that the porosity has a great influence on the light transmittance while the coefficient of variation and the diameter ratio have small ones. Moreover, the influence of the normalized curvature is little. Besides, the effect of the wavelength of visible light can not be ignored. With the simulation, the depth of visible light entering the porous silica can be estimated, which is challenging to access experimentally.

Three-dimensional transition metal hydroxide monoliths were facilely fabricated by a sol-gel process accompanied by phase separation in the presence of polyacrylic acid (PAA) and propylene oxide (PO). In the typical ZnCl 2 -PAA-PO system, PAA is used as a phase separation inducer as well as a framework former to control the phase separation and the formation of macrostructures, whereas PO works as a proton scavenger to initiate the gelation of the system and freeze the macrostructures. Appropriate amount of PAA, PO and solvents allow the formation of zinc (Zn) hydroxide monolith with cocontinuous skeletons and interconnected macropores, and the construction mechanism and characteristics of macrostructure are also investigated. The resultant dried gels are amorphous Zn hydroxide monolith with a narrow macropore size distribution (~1 μm). This approach is further used to successfully prepare macroporous single or binary composite transition metal hydroxide monoliths.

Designing elaborate nanostructures and engineering defects have been promising approaches to fabricate cost-efficient electrocatalysts toward overall water splitting. In this work, a controllable Prussian-blue-analogue-sacrificed strategy followed by an annealing process to harvest defect-rich Ni-Fe-doped K 0.23 MnO 2 cubic nanoflowers (Ni-Fe-K 0.23 MnO 2 CNFs-300) as highly active bifunctional catalysts for oxygen and hydrogen evolution reactions (OER and HER) is reported. Benefiting from many merits, including unique morphology, abundant defects, and doping effect, Ni-Fe-K 0.23 MnO 2 CNFs-300 shows the best electrocatalytic performances among currently reported Mn oxide-based electrocatalysts. This catalyst affords low overpotentials of 270 (320) mV at 10 (100) mA cm -2 for OER with a small Tafel slope of 42.3 mV dec -1 , while requiring overpotentials of 116 and 243 mV to attain 10 and 100 mA cm -2 for HER respectively. Moreover, Ni-Fe-K 0.23 MnO 2 CNFs-300 applied to overall water splitting exhibits a low cell voltage of 1.62 V at 10 mA cm -2 and excellent durability, even superior to the Pt/C||IrO 2 cell at large current density. Density functional theory calculations further confirm that doping Ni and Fe into the crystal lattice of δ-MnO 2 can not only reinforce the conductivity but also reduces the adsorption free-energy barriers on the active sites during OER and HER., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

With polyol-synthesized silver nanoparticles (AgNPs) as raw materials, the silver electrodes with high conductivity were fabricated via a dip-coating method followed by sintering process, and the effects of the dip-coating and sintering process on the conductivity and surface roughness of silver electrodes were investigated in detail. The silver film with a thickness of 1.97 µm and a roughness of about 2 nm can be prepared after dip-coating at a pulling rate of 500 µm s -1 for 40 coating times. The non-conductive dip-coated silver films are transformed into conductive silver electrodes after conventional sintering in a muffle oven, infrared sintering and microwave sintering, respectively. Compared with high sintering temperature and long sintering time of conventional sintering and infrared sintering, microwave sintering can achieve quick sintering of silver films to fabricate high conductive silver electrodes. The silver electrodes with a sheet resistance of 0.75 Ω sq -1 and a surface roughness of less than 1 nm can be obtained after microwave sintering at 500 W for 50 s. The adjustable dip-coating method followed by quick microware sintering is an appropriate approach to prepare high conductive AgNPs-based electrodes for organic light-emitting diodes or other devices., Competing Interests: We declare we have no competing interests., (© 2020 The Authors.)

With methylsilsesquioxane (MSQ) aerogels synthesized by the sol-gel method as a raw material and Si-Ti sol as a binder, an alcohol-based aerogel slurry consisting of only MSQ aerogel and Si-Ti sol was prepared and coated on expanded polytetrafluoroethylene (ePTFE) to form an MSQ aerogel coating layer, followed by low-temperature heat treatment. The effect of Si-Ti sol content on the microstructure of the MSQ aerogel coating layer was investigated, and the properties of a typical MSQ aerogel-layer-coated ePTFE film were evaluated. The results show that Si-Ti sol has an important role in terms of film-forming capability, surface smoothness, flexibility, and powder dropping of the MSQ aerogel coating layer. With a Si-Ti sol of 10.5 wt.% content as a binder and after heat treatment at 170 °C for 30 min, the coated ePTFE flexible thin film with a layer thickness of 30 μm shows high uniformity, integrity, and electrical insulation properties, with an elongation at break decrease over 130%, a thermal conductivity of 0.1753 W/(m·K) at 25 °C, a dielectric constant of 16.5674, and a dielectric loss of 0.06369, which can be promisingly applied in cable sheaths.

Methylsilsesquioxane (MSQ) aerogels with uniform mesopores were facilely prepared via a sol⁻gel process followed by microwave drying with methyltrimethoxysilane (MTMS) as a precursor, hydrochloric acid (HCl) as a catalyst, water and methanol as solvents, hexadecyltrimethylammonium chloride (CTAC) as a surfactant and template, and propylene oxide (PO) as a gelation agent. The microstructure, chemical composition, and pore structures of the resultant MSQ aerogels were investigated in detail to achieve controllable preparation of MSQ aerogels, and the thermal stability of MSQ aerogels was also analyzed. The gelation agent, catalyst, solvent, and microwave power have important roles related to the pore structures of MSQ aerogels. Meanwhile, the microwave drying method was found to not only have a remarkable effect on improving production efficiency, but also to be conducive to avoiding the collapse of pore structure (especially micropores) during drying. The resulting MSQ aerogel microwave-dried at 500 W possessed a specific surface area up to 821 m²/g and a mesopore size of 20 nm, and displayed good thermal stability.

Robust graphene/silver nanowires (AgNWs) hybrid aerogels were fabricated by facile processes including mixing directly, reducing, and ambient pressure drying. The mechanical properties and electromagnetic interference (EMI)-shielding performance of the resultant hybrid aerogels were investigated in detail. Because silver nanowires with a high aspect ratio have been acting as crosslinkers to bridge two-dimensional graphene sheets, a highly porous and electrically conducting framework can resist high external loading to prevent major deformation and act as an express way for electron transport. Consequently, the hybrid aerogel exhibits large mechanical strength of 42 kPa, 35 times larger than that of the neat reduced graphene oxide aerogel (1.2 kPa), which can resist great damage. More importantly, the as-prepared aerogel possesses high EMI-shielding performance of up to ∼45.2 dB due to its unique nanostructure and good electrical properties. These results indicate that graphene/AgNWs hybrid aerogel prepared using this simplified method promises to be an ideal functional component for mechanically robust and high-performance EMI-shielding nanocomposites., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

New flexible methylsilsesquioxane (MSQ) aerogels have been facilely prepared by a sol-gel process with methyltrimethoxysilane (MTMS) and dimethyldimethoxysilane (DMDMS) as co-precursors, followed by surface modification and ambient pressure drying. The microstructure, mechanical properties and hydrophobicity of these MSQ aerogels after surface modifications of hexamethyldisiloxane (HMDSO) and/or hexamethyldisilazane (HMDS) were investigated in detail, and the applications of surface-modified MSQ aerogels in sound-absorbance, fast dye adsorption and oil/water separation were evaluated, respectively. The MSQ aerogels surface-modified by HMDS possess flexibility, elasticity and superhydrophobicity, and demonstrate good performance in the mentioned applications. The resultant MSQ aerogel used in sound-absorbance has high frequency (about 6 kHz) acoustic absorptivity of up to 80%, benefiting from its macroporous structure and porosity of 94%, and it also possesses intermediate frequency acoustic absorptivity (about 1 kHz) up to 80% owing to its elasticity. This MSQ aerogel can selectively separate oil from oil/water mixtures with high efficiency due to its superhydrophobicity and superlipophilicity, resulting from a lot of methyl groups, density as low as 0.12 cm³·g -1 and a water contact angle as high as 157°. This MSQ aerogel can be assembled to be a monolithic column applied for fast dye adsorption, and shows selective adsorption for anionic dyes and removal efficiency of methyl orange of up to 95%., Competing Interests: The authors declare no conflict of interest.

Silver nanowires (AgNWs) thin films have emerged as promising next-generation transparent conductive electrodes (TCEs), and increasing the opto-electrical properties and long-term stability of AgNWs based TCEs is now a major research focus. In this work, a smooth, flexible, electrically conductive and highly stable transparent AgNWs-silica nanoparticles composite TCE has been successfully manufactured via coating an aqueous AgNWs-silica sol composite conductive ink on a PET substrate through the Mayer rod method. The effects of particle size and concentration of silica sol on the smoothness, opto-electrical properties and stability of AgNWs based TCEs were investigated in detail, and the mechanisms of the decoration of AgNWs by silica sol nanoparticles and welding of the network junction are discussed briefly. The TCE based on AgNWs reinforced with 50 nm silica nanoparticles (80 ppm concentration of silica sol) possesses a smooth surface with an RMS value of 9.45 nm, and superior opto-electrical properties with a sheet resistance of 28 Ω sq -1 and a transmittance of 97%. The resistance of the resultant AgNWs-silica composite TCE remains nearly constant after bending for 1000 cycles or exposure to Na 2 S solution for 300 s, indicating high stability. The newly designed AgNWs-silica composite TCE is a promising flexible and transparent electrode to be applied in next-generation flexible electronic devices., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Room-temperature stable macroporous mayenite electride (C12A7:e - ) has been successfully prepared via a sol-gel method accompanied by phase separation, followed by heat-treatment and reduction processes. The obtained xerogel monoliths possess controllable macrostructure and a porosity of more than 60%, depending on adjusting the amount of poly(ethylene oxide) as a phase separation inducer. Heat-treatment allows the formation of multicrystals Ca 12 Al 14 O 32 Cl 2 and Ca 12 Al 14 O 33 (C12A7), and the porosity increases to 78.67% after being heat-treated at 1100 °C. Further reduction promotes the transformation from Ca 12 Al 14 O 32 Cl 2 or C12A7 to C12A7:e - as well as the conversion from an insulator to a semiconductive electride. The carrier concentration of the electride reaches 3.029 × 10 18 cm -3 after being reduced at 1100 °C under Ar atmosphere, and the porosity still remains 66%. The macrostructure of the resultant mayenite electride before and after heat-treatment and reduction is perfectly preserved, indicating that the obtained macroporous monolithic mayenite electride could be utilized in the electronic components., Competing Interests: The authors declare no competing financial interest.

Mesoporous silica microspheres were synthesized by an acid-catalyzed sol-gel method using tetraethoxysilane (TEOS) as a precursor. The hydrochloric acid was used as a catalyzer to induce the hydrolysis of TEOS, while the cyclohexane acted as a stabilizer of the sol. The addition of polyethylene glycol can introduce the uniform mesoporous structure into the microspheres by phase separation. The as-prepared mesoporous silica microspheres possess a narrow particle size distribution, a mesopore size of 5.0 nm and a Brunauer-Emmett-Teller specific surface area as high as 230 m2·g-1. The resultant silica microspheres were used for packing chiral high-performance liquid chromatography (HPLC) columns, after activated by hydrochloric acid and modified by amylose-tris(3,5-dimethylphenylcarbamate), respectively. The flurbiprofen axetil as a typical chiral drug with two stereocenters can be successfully separated by the as-obtained chiral HPLC columns using different mobile phases., (© The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Hierarchically porous silica monoliths with well-defined interconnected macropores and uniform spherical mesopores were spontaneously prepared by combining polymerization-induced phase separation with an epoxide-mediated sol-gel route without any complicated aging and drying and high-temperature heat treatment. The precise control of pore structures can be realized by using propylene oxide (PO) as the gelation mediation agent, poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (P123) as the phase-separation inducer as well as the structure-directing agent and 1,3,5-trimethylbenzene (TMB) as the micelle-swelling agent. The as-prepared silica monolith possesses an interesting hierarchically porous structure constructed by 10 nm uniform spherical mesopores confined in a macroporous framework of well-defined 1 μm macropores, and exhibits a BET surface area as high as 848 m(2) g(-1). Heat treatment at 400-800 °C gradually decreases the BET surface area to 195 m(2) g(-1), while most of the uniform mesoporous structure remains intact.

Monolithic macroporous zirconia (ZrO 2 ) derived from ionic precursors has been successfully fabricated via the epoxide-mediated sol-gel route accompanied by phase separation in the presence of propylene oxide (PO) and poly(ethylene oxide) (PEO). The addition of PO used as an acid scavenger mediates the gelation, whereas PEO enhances the polymerization-induced phase separation. The appropriate choice of the starting compositions allows the production of a macroporous zirconia monolith with a porosity of 52.9% and a Brunauer-Emmett-Teller (BET) surface area of 171.9 m 2 · g -1 . The resultant dried gel is amorphous, whereas tetragonal ZrO 2 and monoclinic ZrO 2 are precipitated at 400 and 600 °C, respectively, without spoiling the macroporous morphology. After solvothermal treatment with an ethanol solution of ammonia, tetragonal ZrO 2 monoliths with smooth skeletons and well-defined mesopores can be obtained, and the BET surface area is enhanced to 583.8 m 2 · g -1 .

A facile and "green" method was proposed to introduce Ag nanoparticles (Ag NPs) into the hierarchically monolithic silica uniformly in the presence of (3-aminopropyl)-triethoxysilane (APTES) and ethylene glycol. APTES is used to modify the monolith by incorporating amino groups onto the surface of meso-macroporous skeletons, while ethylene glycol is employed as the productive reductant. Ag NPs are homogeneously immobilized in hierarchically monolithic silica after reduction and drying at 40 °C for different duration times, and the embedded amount of Ag NPs can reach 15.44 wt% when treated once. The embedment of Ag NPs increases with the repeat treatment and the APTES amount, without uncontrollable crystalline growth. The surface areas of Ag NPs embedded in silica monoliths after heat treatment at 300 and 400 °C are higher than those before heat treatment. The modification via APTES and the embedment of Ag NPs does not spoil the morphology of monolithic silica, while changing the pore structures of the monolith. A tentative formation process and a reduction mechanism are proposed for the modification, reduction and embedment. Ag NPs embedded in monolithic silica is promising for wide applications such as catalysis and separation.

The product of the MDMX (or MDM4) gene is structurally related to the MDM2 oncoprotein and is also capable of interacting with the tumor suppressor protein p53. The MDM4 gene is overexpressed in several human tumors, while its product can be detected as various isoforms. This study was aimed to find the presence of aberrant mRNA transcripts of MDM4 in human glioma and their association with the clinicopathological characteristics of glioma patients. 42 glioma tissues were examined for MDM4 mRNA splicing variants by RT-PCR. A total of four distinct transcript sizes (full length-MDM4 851 bp, MDM4-S 783 bp, MDM4-A 701 bp, MDM4-B 540 bp) were detected. In the present study, we first report the novel alternative splicing form of MDM4, MDM4-B (GenBank accession no.KC479043.1). Expression of MDM4-B was present in various stages of human gliomas, but no significant correlation between presence of MDM4-B and malignancy of glioma was observed. The expression level of MDM4-B mRNA detected by real-time PCR was not only significantly associated with tumor stages, but also with p53 mutation and Ki-67 status which are important clinical molecular markers of glioma. Our data indicate that the novel variant MDM4-B may play a role in glioma tumorigenesis or cancer progression., (© 2013 Elsevier B.V. All rights reserved.)

Monolithic aluminum phosphate (AlPO 4 ) with a macro-mesoporous structure has been successfully prepared via the sol-gel process accompanied by phase separation in the presence of poly(ethylene oxide) (PEO). Gelation of the system has been mediated by propylene oxide (PO), while PEO induces a phase separation. The dried gel is amorphous, whereas the crystalline tridymite phase precipitates upon heating above 1000 °C. Heat treatment does not spoil the macroporous morphology of the AlPO 4 monoliths. Nitrogen adsorption-desorption measurements revealed that the skeletons of the dried gels possess a mesostructure with a median pore size of about 30 nm and a surface area as high as 120 m 2 g -1 . Hydrothermal treatment before heat treatment can increase the surface area to 282 m 2 g -1 .

Brevican is the most abundant chondroitin sulfate proteoglycan in the extracellular matrix (ECM) of the adult rat brain. It has been found only in the central nervous system (CNS). In this study, we found that secreted brevican transcript was detectable in the pituitary of both male and female adult rats by reverse transcriptase-polymerase chain reaction (RT-PCR) amplification. In posterior lobe of pituitary, pituicytes were heavily labelled. In anterior and intermediate lobes of pituitary, signals for brevican transcripts were observed in cells of various sizes. These data demonstrated that secreted brevican mRNA is expressed in the adult rat pituitary and brevican might not be a CNS-specific ECM.