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The high integration density of microelectronic devices leads to local heat accumulation, and effective heat dissipation and signal transmission of packaging materials have become the primary issues to be solved. However, existing polymer materials have difficulty meeting the requirements due to their unsatisfactory thermal conductivity and thermal expansion properties. In this work, we proposed the use of digital light processing (DLP) printing technology to construct a triply periodic minimum surface (TPMS) skeleton, and a continuous and efficient heat conduction path was successfully constructed in epoxy resin by impregnating h-BN on the skeleton surface. When the loading of h-BN was 20 vol%, the thermal conductivity of the TPMS(SiO 2)@BN/EP(BN) composites was 1.86 W/(m·K), which was 786 % higher than that of pure epoxy resin. In addition, the thermal expansion coefficient of the composites decreased by more than 70 %. At the test frequencies of 3∼10 MHz, the composites showed stable dielectric properties, and the dielectric constant was always maintained in a low range, between 3.85 and 4.15. This work has realized the transformation of the method for constructing a heat conduction path from disordered to ordered and from random to repeatable. This provides a new strategy for the selection of microelectronic packaging materials. [ABSTRACT FROM AUTHOR]

A three dimensional (3D) reduced graphene oxide (rGO)/zeolitic imidazolate framework-67(ZIF-67) aerogel (3D rGO/ZIF-67 aerogel) was prepared via in situ assembly of ZIF-67 polyhedrons on a 3D rGO networks, not only providing multifarious affinity interactions for synergistic promoting the adsorption behavior of organic dyes, but also constructing a holder for ZIF-67 polyhedrons to convenient separation. This porous aerogel displays excellent absorption ability for cationic dyes (crystal violet, CV) and anionic dyes (methyl orange, MO). The maximum adsorption capacities are up to 1714.2 mg·g −1 and 426.3 mg·g −1 for CV and MO, respectively. 3D rGO/ZIF-67 aerogel shows a remarkable promoting of CV adsorption capacity than pure 3D rGO and ZIF-67. The ultrahigh adsorption capability towards cationic CV dyes is mainly driven by π-π interactions and electrostatic interactions between 3D rGO/ZIF-67 aerogel and dye molecules, and synergistic interactions at the interface of 3D rGO and ZIF-67 polyhedrons. The high adsorption capability towards anionic MO dyes is mainly due to the porosity of ZIF-67 polyhedrons and electrostatic attraction between MO and ZIF-67. The multi-component property of 3D rGO/ZIF-67 aerogel shows a great potential application in dye-bearing wastewater treatment. [ABSTRACT FROM AUTHOR]

Three linear push-pull compounds comprised of difluoroboron β-diketonate and triphenylamine unit 4,6-Bis(4-(diphenylamino)phenyl)-2,2-difluoro-2H-1,3,2-dioxaborinin-1-ium-2-uide, (E)-6-(4-(Diphenylamino)phenyl)-4(4(diphenylamino)styryl)-2,2-difluoro-2H-1,3,2-dioxaborinin-1ium-2-uide and 4,6-Bis((E)-4-(diphenylamino)styryl)-2,2-difluoro-2H-1,3,2-dioxaborinin-1-ium-2-uide (ABA, ABVA, and AVBVA) have been probed by many spectroscopies. The results clarify the photo-physical property of the compounds where ABVA and AVBVA are linked with vinyl units (V). The solvent-dependent steady absorption and photoluminescence spectra data shows that the vinyl unit and the polarity of the solvent influence the photo-physical properties of the compound. Moreover, the vinyl unit would further enhance the role of the polar environment. The transient absorption measurement then offers excitation relaxation behavior. The results show that excited compounds in cyclohexene go back to the ground state through the intramolecular charge transfer (ICT) state, and the transfer lifetime from the initial excited state to the ICT state would prolong after the introduction of vinyl unit. The relaxation behavior becomes complex when cyclohexene is replaced by tetrahydrofuran. Some excited compounds go directly back to the ground state and others go back to the ground state after passing through the ICT state. In addition, two-photon PL measurements and a Z-scan technique are employed, and this confirms that these compounds have two-photon behavior, but the two-photon absorption section gradually decreases. This decrease is attributed to the spectral shifting affected by the vinyl unit. [ABSTRACT FROM AUTHOR]

Through comparing the linear and nonlinear optical property of two pull-push chromophores, which are composed of difluoroboron β-diketonate functionalized with carbazole and tert-butyl carbazole, the role of tert-butyl in chromosphere has been discussed in detail. The tert-butyl unit would lead to the absorption and fluorescence peak red shift and accelerate the fluorescence relaxation rate of chromophores. Moreover, the tert-butyl unit would affect obviously the two-photon optical property of chromophore according to the Z-scan test. The transient absorption (TA) data shows that these two pull-push chromopphores both own intramolecular charge transfer (ICT) characteristics and the tert-butyl unit accelerate the dynamic rate of ICT generation and relaxation process, which may be responsible for the variance of fluorescence property. [ABSTRACT FROM AUTHOR]

The design and preparation of hierarchical porous transition metal oxide-carbon matrix anodes with unique structure play the significant role in highly reversible lithium ion batteries. Herein, hierarchical porous wheat-like Co 3 O 4 on carbon derived from natural silk (named as SK@Co 3 O 4) nanobelts are fabricated successfully by one-step hydrothermal technique and ensuing high-temperature calcination. The wheat-like SK@Co 3 O 4 nanobelts consist of a number of nanobeams. The length of nanobelts is around 1 µm whereas the diameter is 200 nm. Moreover, the SK@Co 3 O 4 anode for lithium ion batteries retains 1108 mA h g−1 following 100 cycles at 100 mA g−1, 707 mA h g−1 and 709 mA h g−1 after 150 cycles at 2 A g−1, 625 mA h g−1 and 617 mA h g−1 after 150 cycles at 5 A g−1,which show extraordinary cycle stability of the composite. The remarkable lithium storage property results from the hierarchical porous structure and this structure can not only provide a short ion transport path but also raise the area of contact between the electrolyte and electrode. [Display omitted] • Wheat-like Co 3 O 4 on carbon derived from silk was synthesized. • Silk was used as carbon source. • SK@Co 3 O 4 nanobelts showed high lithium storage performance. [ABSTRACT FROM AUTHOR]

A Cu-coated Al 2 O 3 substrates which can be used for power modules are prepared via sintering and reduction of CuO–SiO 2 film onto the surface of Al 2 O 3 ceramic without precious metal brazing filler or high-vacuum equipment. This method has a significant cost advantage over the existing technology. Effects of oxygen partial pressure from sintering atmosphere and SiO 2 content on microstructure and mechanical properties of Cu/Al 2 O 3 interface are systematically investigated. Phase compositions and morphologies of sintered Cu 2 O layer, reduced Cu layer and reactive layer are characterized via X-ray diffraction and scanning electron microscopy. In addition, physicochemical changes within CuO–SiO 2 during sintering are characterized by thermogravimetry-differential scanning calorimeter. It is found that oxygen and SiO 2 can promote the generation of Cu 2 O–CuO–SiO 2 eutectic phase with low melting point upon sintering, which increases the thickness of reaction layer and the densification of Cu layer. The shear strength between the Cu layer and the Al 2 O 3 substrate is enhanced with the increase in Cu layer densification degree, while varying in irregular manner with the thickness of reaction layer. In particular, the highest shear strength of 62.70 MPa is obtained at oxygen partial pressure of 0.02 atm and SiO 2 content of 1.5 wt%. [ABSTRACT FROM AUTHOR]

The removal of organic contaminants from water poses a significant challenge that can be tackled by integrating adsorption and photocatalytic degradation functions in a single architecture. However, traditional powdery nanomaterials face challenges in separation and lack synergistic function, hampering their practical application. This study presents a one-step hydrothermal synthesis of a convenient recyclable Bi 2 O 2.33 /Bi 2 O 3 @ECNF (electrospun carbon nanofibers), which combines both adsorption and photocatalytic performance. The Bi 2 O 2.33 /Bi 2 O 3 exhibits high adsorption removal of methyl orange (MO), reaching 94.56 % and a maximum capacity of 213.13 mg g−1. Additionally, the Bi 2 O 2.33 /Bi 2 O 3 shows a high charge transfer rate, strong redox ability, and efficient removal of Rhodamine B (RhB) at 83.01 %. Loading the Bi 2 O 2.33 /Bi 2 O 3 on lightweight carbon fibers allows for easy recycling. The Bi 2 O 2.33 /Bi 2 O 3 @ECNF demonstrates excellent stability and reusability, with a removal rate of 87.37 % for tetracycline hydrochloride (TCH) at high concentrations. This work presents a promising solution for the practical application of photocatalysts by overcoming the limitations of single photocatalysts and minimizing secondary pollution from single adsorbents. [Display omitted] [ABSTRACT FROM AUTHOR]

Regeneration serves as a self-protective mechanism that allows a tissue or organ to recover its entire form and function after suffering damage. However, the regenerative capacity varies greatly within the plant kingdom. Primitive plants frequently display an amazing regenerative ability as they have developed a complex system and strategy for long-term survival under extreme stress conditions. The regenerative ability of dicot species is highly variable, but that of monocots often exhibits extreme recalcitrance to tissue replenishment. Recent studies have revealed key factors and signals that affect cell fate during plant regeneration, some of which are conserved among the plant lineage. Among these, several members of the ETHYLENE RESPONSE FACTOR (ERF) transcription factors have been implicated in wound signaling, playing crucial roles in the regenerative mechanisms after different types of wounding. An understanding of plant regeneration may ultimately lead to an increased regenerative potential of recalcitrant species, producing more high-yielding, multi-resistant and environmentally friendly crops and ensuring the long-term development of global agriculture. [ABSTRACT FROM AUTHOR]

As a skin-resident member of the dendritic cell family, Langerhans cells (LCs) are generally regarded to function as professional antigen-presenting cells. Here we report a simple method to visualize the endocytotic activity of LCs in living animals. BALB/c mice received subcutaneous injection of FITC-conjugated dextran (DX) probes into the ear skin and were then examined under confocal microscopy. Large numbers of FITC+ epidermal cells became detectable 12-24 hours after injection as background fluorescence signals began to disappear. Most (>90%) of the FITC+ epidermal cells expressed Langerin, and >95% of Langerin+ epidermal cells exhibited significant FITC signals. To assess intracellular localization, Alexa Fluor 546-conjugated DX probes were locally injected into IAβ-enhanced green fluorescent protein (EGFP) knock-in mice and Langerin-EGFP-diphtheria toxin receptor mice-three dimensional rotation images showed close association of most of the internalized DX probes with major histocompatibility complex (MHC) class II molecules, but not with Langerin molecules. These observations support the current view that LCs constantly sample surrounding materials, including harmful and innocuous antigens, at the environmental interface. Our data also validate the potential utility of the newly developed imaging approach to monitor LC function in wild-type animals. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents novel organogelators based on long chain substituted benzoic acid hydrazine which can form stable gels in bulk organic solvents and self-assemble into various microstructures in organogel phases. It is found that hydrogen bonding and van der Waals interaction play an important role on the formation of organogel. [Copyright &y& Elsevier]

• Superhydrophilic nanostructure was fabricated for improving soft tissue sealing. • The properties of the surface regulate the behavior of human gingival fibroblasts. • FAK/integrin-mediated adhesion seemed to be induced by the hydrogenated surface. Soft tissue integration is critical for the long-term retention of dental implants. The surface properties including topography and wettability can impact soft tissue sealing. In our work, a thermal hydrogenation technique was applied to modify anodized titanium dioxide nanotubes (TNTs). However, the effects of the hydrogenated surface on soft-tissue cells remain unclear. The aim of the present study was to investigate the bioactivities of human gingival fibroblasts (HGFs) on structured surfaces, which determine the early formation of soft tissue sealing. Three groups were examined: commercially pure titanium (Ti), anodized TNTs (air-TNTs) and hydrogenated TNTs (H 2 -TNTs). Scanning electron microscopy showed the nanotubular topography on the titanium surfaces after anodization. Then, hydrogenation ensured that the H 2 -TNTs were superhydrophilic with a contact angle of 3.5 ± 0.8°. In vitro studies such as cell adhesion assays, cell morphology, immunocytochemistry, wound healing assays, real-time PCR and enzyme-linked immunosorbent assays displayed enhanced adhesion, migration, relative gene expression levels, and extracellular matrix synthesis of the HGFs on H 2 -TNTs. Interestingly, focal adhesion kinase activation and integrin-mediated adhesion seemed to be induced by the H 2 -TNT surface. Our results revealed that a superhydrophilic nanostructure modified by anodization and hydrogenation can improve the bioactivity of HGFs and connective tissue regeneration, which will further promote and expand the application of titanium dioxide nanotubes in dental implants. [ABSTRACT FROM AUTHOR]

Efficacious and convenient removal of organic dye contaminants from wastewater is a challenge for public health and ecosystem protection. Here we fabricate a novel type of Fe 3 O 4 @MOFs (Metal-organic frameworks) magnetic porous composite materials. ZIF-67 (Zeolitic imidazolate framework-67) nano-crystals as an attractive subfamily of MOF was selected to fabricate Fe 3 O 4 -PSS@ZIF-67 composites (defined as MZIF-67). MZIF-67 composites are core-shell structure, for which the aggregation core of Fe 3 O 4 nanoparticles is coated with petal-like ZIF-67 crystals, in which Co 2+ firstly combines with SO 3 2− provided by PSS (poly (styrenesulfonate, sodium salt)) to form nucleation. MZIF-67 composites perform well on methyl orange (MO) adsorption, which could be attributed to the highly porosity and the nature of Lewis base of coordinated Co 2+ centrals. The results show that the equilibrium adsorption capacity for MO is up to 738 mg·g −1 (when pH = 8.0, contact time is 7 h, adsorbent dose is 5 mg and initial MO concentration is 400 mg·L −1 ). In addition, MZIF-67 composites could selectively separate MO from the mixture solution of MO and MB (methylene blue). The removal rate of MO is up to 92%. The concentration ratio of MO/MB is 0.04. And the separation efficiency is up to 96%. The results suggest MZIF-67 composites could be a good candidate for treatment of dye-bearing wastewater. [ABSTRACT FROM AUTHOR]

Two push-pull compounds, which are comprised of triphenylamine (TPA) (electron donor units) and functionalized β-diketones difluorboron complexes (electron acceptor units) are probed by many spectroscopies, which offers the relationship between electron acceptor and the intrinsic excited state properties of push–pull chromophores. We found that the photoluminescence (PL) intensity would enhance with the number of electron acceptor. Transient absorption (TA) data shows that intramolecular charge transfer (ICT) process really exists in the two molecules after photoexcitation and this process would be prolonged through increasing the electron-acceptor, which would be responsible for the improvement of PL property. [ABSTRACT FROM AUTHOR]

[Display omitted] • An all-in-one MoS 2 -based electrocatalyst for hydrogen evolution is constructed by inkjet printing. • Inkjet-printed 3D architecture contributes to the exposure of active catalytic sites. • 1T-MoS 2 surrounded by graphene reduces the charge-transfer impendence. • Cu contact supports the efficient electron injection from the electrode to catalytic materials. • The facile and scalable avenue allows the fabrication of electrocatalysts with high throughput. 2D transition metal dichalcogenides (TMDs) are emerging as promising alternative electrocatalysts for hydrogen evolution reaction (HER). However, key challenges are the limited density of available activity sites and poor electron accessibility. Herein, Cu film supported MoS 2 -based electrocatalyst with partial 1T phase and 3D architecture is constructed by inkjet printing. We aim to investigate if this configuration could provide largely exposed edge sites and enhance electron transfer for ultra-efficient hydrogen production. Towards this end, an ink containing few-layer MoS 2 nanosheets and reduced graphene oxide (RGO) is firstly prepared by liquid-phase exfoliation, in which semiconducting 2H-MoS 2 is partially transformed to metallic 1 T-MoS 2. We demonstrate that 1) nanosized few-layer MoS 2 spatially patterned by inkjet-printing provides sufficient active site exposure, 2) the 1T-MoS 2 and RGO conductive network reduce the charge-transfer impedance, and 3) the Cu support enhances the catalyst-electrode charge injection. Our all-in-one structure exhibits outstanding HER activities with low overpotential (51 mV at 10 mA cm−2 and 126 mV at 100 mA cm−2) and very low Tafel slope (32 mV dec-1). Also, the as-engineered electrode demonstrates ultrahigh cathodic current density. This work provides a facile, inexpensive, and scalable way for designing and fabricating TMDs-based electrocatalysts with excellent HER activity. [ABSTRACT FROM AUTHOR]

Zebrafish Fish-egg lectin (zFEL) has been identified and proved to be a maternal factor with antibacterial and opsonic ability in fishes. In this study, we found that zFEL was capable of enhancing the phagocytosis of the bacteria by macrophages of mouse (RAW264.7 and mouse peritoneal macrophages), suggesting a cross-species function of zFEL in higher animals. Further studies showed that zFEL can active the antigen presentation ability by up-regulating the expression of CD80, CD86 and MHC II. Meanwhile, zFEL also promoted the polarization of macrophages to M1-type, which was confirmed by the increase of cytokines TNF-α and IL-6. The expression of p38 gene was up-regulated in macrophages preincubated with zFEL. Taken together, zFEL appears opsonic function in mammal macrophages and has potential application in immunomodulation. • Cross-species opsonic activity is found by zebrafish fish-egg lectin (zFEL) on mouse macrophages. • zFEL can up-regulate the expression of CD80, CD86 and MHC II on macrophages. • zFEL promotes the polarization of macrophages to M1-type. [ABSTRACT FROM AUTHOR]

Abstract: A modified sol–gel method was used to synthesize single-crystalline lead-free (K,Na)NbO3 (KNN) nanorods. The effects of calcination temperature and heating rate on the crystal structure and morphology were examined. At low heating rate, it was found that with increasing calcination temperature, the crystallization of KNN gradually completed and the size of the one-dimensional rods increased significantly. On the other hand, increasing heating rate changed the morphology of KNN from one-dimensional rods to cubes. The as-synthesized KNN nanorods calcined at 750°C with heating rate of 1°C/min were determined to be orthorhombic single crystals of 100–400nm wide and 1–2μm long. [Copyright &y& Elsevier]

Highlights: [•] π-Spacer dependent optical properties of fluorenone-based oligomers are studied. [•] Fluorene–ethylene (FE) spacer could modulate the steady-state spectra of oligomers. [•] DFT calculations confirm the ICT nature in the HOMO–LUMO transition. [•] FE spacer could increase the TPPL efficiency and TPA cross-section of oligomers. [•] TA measurement confirms the ICT state exists in the relaxation of excited oligomer. [Copyright &y& Elsevier]

Abstract: Lead zirconate titanate (PZT) based piezoelectric composites embedded with ZnO nanowhiskers (ZnOw) were investigated to clarify the optimal sintering condition for densification, microstructure, and electrical properties. The samples are characterized by X-ray diffraction analysis and scanning electron microscopy. The results show that the increase of the sintering temperature and time is quite effective in improving the densification and piezoelectric properties of the PZT/ZnOw composites. However, the relative density and piezoelectric properties deteriorate as the composites are sintered over the optimal sintering condition. Particularly, the PZT/ZnOw composites sintered at 1150°C for 2h show excellent electrical properties of piezoelectric constant d 33 ∼471pC/N, relative dielectric constant ɛ ∼3838, planar electromechanical coupling factor k p ∼0.543, remnant polarization P r ∼23.2μC/cm2 and coercive field E c ∼9.2kV/cm. [Copyright &y& Elsevier]