Search

Extensive efforts have been made to investigate energy conversion process based on metal-semiconductor Schottky junctions. In this study we report the exploration of electricity generation through water evaporation on the surface with double Schottky junctions of symmetric design. By using such symmetric Schottky junctions at both side of a silicon wafer, the electricity generation is enhanced over the system with just a single Schottky junction. In the symmetric-junction system, water evaporation on the surface of one Schottky junction breaks the symmetry, leading to the generation of a continuous and direct current. The evaporation-induced cooling and continuous liquid-solid contact electrification at the Schottky junction on one side of the system enable the fast flow of the hot electrons across the Schottky junction on the other side. This work not only demonstrates a continuous and direct-current generation system, which has the potential of harvesting a broad range of waste heat and enabling many promising applications, but also offers a general strategy using the symmetric design of Schottky junctions to enhance electricity generation in diverse energy conversion systems. [Display omitted] • Symmetric double Schottky junction based device shows enhanced electricity generation during water vaporization. • Cooling and contact electrification during the water vaporization process synergistically enable the enhanced electricity generantion. • The maximum continuous and direct-current density of ∼ 1 A m–2 and peak power density of 13 mW m–2 were achieved. [ABSTRACT FROM AUTHOR]

Direct absorption-based solar collectors, which rely on volumetric absorption of sunlight by optical nanofluids, have emerged as a superior way to conventional surface absorption-based collectors for harvesting solar-thermal energy. In this short review, we summarize the recent progress on preparing medium-to-high-temperature solar-thermal nanofluids that can be potentially used in direct absorption-based solar collectors under concentrated solar fluxes. Emphasis is placed on discussing the challenge and strategies to achieve stable dispersion of the optical nanofluids. [ABSTRACT FROM AUTHOR]

Nanobubbles have attracted significant attention in recent years for their potential applications in various fields, including engineering, environmental, biological, and medical. Furthermore, different types of nanobubbles are used for different fields due to their distinct properties. Yet, the challenge remains to understand the growth kinetics of both interfacial and bulk nanobubbles at the nanoscale to meet the requirements of different applications. Using liquid cell transmission electron microscopy, we revealed a quasi-equilibrium state in the growth trajectory of nanobubbles induced by the electron beam in the aqueous solution in real-time. Specifically, we successfully distinguished between interfacial and bulk nanobubbles by combining the analysis of growth kinetics and the Fresnel fringe method. Furthermore, the non-equilibrium growth of some nanobubbles from solution to the interface was revealed by the above method. These insights on the nanoscale growth kinetics of nanobubbles can help better engineer tailored nanobubbles with specific kinetic behaviors for different applications. [Display omitted] • The universal growth trajectories of nanobubbles were revealed by in situ LC-TEM. • The types of nanobubbles (BNBs and INBs) could be distinguished by combining the analysis of growth kinetics and the Fresnel fringe method. • The non-equilibrium growth of BNBs attaching to the interface was monitored and analyzed by this modified process. • The study provided insights into engineering the tailored nanobubbles for the different application fields. [ABSTRACT FROM AUTHOR]

Solar-thermal evaporation of seawater holds the potential for coproduction of freshwater and electricity, but conventional assembled bilayer two-dimensional (2D) evaporators often suffer from low vapor generation rates and poor performance stability. Herein, we report polyvinyl alcohol sponges compounded with poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) and carbon nanotubes as all-in-one 3D dual-functional solar-thermal evaporators for simultaneous high-flux desalination and electricity generation. The sponge composites possess high solar absorptance, hierarchical porous structure, strong anti-salt fouling capability and negatively-charged ionic channels. In particular, the enlarged 3D evaporation surfaces and the low evaporation enthalpy achieved a high evaporation rate of 6.8 kg m−2 h−1 and a high evaporation efficiency of 94.9% under one-sun solar irradiation. The evaporation-induced high-flux directional flow of seawater through the ionic channels within the sponges generate a stable potential of 117.8 mV. By connecting several sponge evaporators in series, we show that the integrated system can stably generate potable freshwater out of seawater under continuous solar irradiation to meet individual drinking need, and simultaneously produce sufficient electricity to power small electronic devices. The stable superior performance, integrated structure design and facile manufacturing process would make the all-in-one 3D sponge evaporators promising for renewable off-grid coproduction of drinkable clean water and electricity. [Display omitted] • 3D sponge evaporators are designed for simultaneous solar-thermal desalination and electricity generation. • A high evaporation rate of 6.8 kg m−2 h−1 and an ion-voltaic potential of 117.8 mV are achieved under one-sun irradiation. • Continuous stable generation of drinkable water and electricity is demonstrated. [ABSTRACT FROM AUTHOR]

Abstract: Zona pellucida binding proteins (ZPBPs) are important receptors of zona pellucida on sperm and play an essential role in sperm–egg interaction. In the present study, the full-length coding regions of transcript variant 1 and 2 of ZPBP2 were cloned in the pig. ZPBP1 gene expression was specifically present in testes of boar reproductive tracts; while ZPBP2 mRNA was detected with highly in testes, moderate in seminal vesicles and low in caudal epididymes. We also examined the expression profile of porcine ZPBP1 and ZPBP2 in testes and seminal vesicles at different developmental stages. The results revealed that ZPBP1 mRNA was not detectable until day 70 and kept relative stable from days 70 to 105, then increased sharply from days 105 to 160 during sexual maturity (P <0.01). ZPBP2 mRNA was detected with relative low level until day 70 and but increased significantly from days 70 to 105 (P <0.01), and increased further from days 105 to 160 during sexual maturity (P <0.01). The data indicated that testes are the main origin of ZPBPs and the expression of ZPBPs are parallel with reproduction development. [ABSTRACT FROM AUTHOR]

[Display omitted] Films with nanoengineered surfaces have found extensive utilization in versatile applications, such as freshwater harvesting, water purification, steam generation and thermal energy management. Herein, we develop a liquid metal (LM) nanoporous film on a copper substrate via a simple and scalable bubble-induced self-assembly method. The LM nanoporous film not only provides abundant nucleation sites of bubbles due to nanoscale pores, but also generates CuGa 2 intermetallic compound (IMC) as a thermal interface layer with low interfacial resistance due to in situ alloying with the copper substrate. When the film is used in ethanol-based boiling system, it shows a 172% enhanced heat transfer coefficient compared to the pristine copper. In addition, the metallic wetting force between the LM nanoporous film and CuGa 2 IMC results in a durable nanoporous film. When the LM nanoporous film is utilized for the phase-change thermal energy management of a high-power-density light emitting diode, it leads to a distinct decrease in temperature by 20.7 ℃ relative to the pristine copper. This work provides a strategy to combine nanoengineered surfaces with interface engineering to enhance phase-change heat transfer, which can result in efficient energy transport in various energy-related applications. [ABSTRACT FROM AUTHOR]

Mesoporous graphene and other carbon derivative nanospheres have attracted intensive research attention owing to their many unique characteristics and fascinating properties. However, facile synthesis of these mesoporous nanospheres with a small particle size and controllable morphology is still a grand challenge. Herein, we report a Kirigami-inspired approach to prepare mesoporous spherical graphene oxide (MSGO) particles through spray drying of holey GO sheets. By increasing pore size and porosity of the holey GO sheets, the spray-dried particles underwent the transition from rough crumpled structure to smooth spherical shape. The prepared MSGO particles have tunable diameters smaller than 200 nm and a high specific surface area of 503 m2/g, which enable consistent high-efficiency physical adsorption removal of organic dyes such as Rhodamine B from polluted water with a high adsorption rate of 335.6 mg/(g min). Moreover, the reported synthetic route provides the freedom to easily incorporate other functional nanoparticles such as TiO 2 , CuO or post-dope MSGO with nitrogen elements for construction of multifunctional composite particles with tailorable structures, which may enable a broad range of promising applications. [Display omitted] • MSGO nanoparticles are synthesized by spray drying holey graphene oxide sheets. • Pore size, porosity, particle size and specific surface area of MSGO particles can be tuned. • High-capacity fast adsorption removal of Rhodamine B by MSGO particles is demonstrated. • Easy integration of other functional materials into MSGO particles is demonstrated. [ABSTRACT FROM AUTHOR]

Direct absorption of sunlight with carbon nanofluids is a facile way to efficiently harvest solar-thermal energy, but poor dispersion stability of nanofluids under elevated temperatures severely limits their applications. Herein, we report a general strategy to prepare stably-dispersed medium-temperature solar-thermal nanofluids by employing crumpled particles of ethanol-wetted graphene oxide sheets as the self-dispersible photothermal converters. The crumpled particles simultaneously possess intensively-deformed surface structure, a low density and a small particle size. Such features weaken the inter-particle van der Waals attraction and gravitational sedimentation of the crumpled particles, thereby enabling their long-term stable dispersion within commercial thermal storage oils. Uniform dispersion of nanofluids was maintained after continuous heating for 2 weeks under a heating temperature up to 200 °C. The homogenously dispersed nanofluids also achieved high solar absorptance with low particle loadings, and retained the large heat capacity and suitable viscosity. These combined advantageous thermophysical properties enabled consistent high-performance medium-temperature direct absorption-based nanofluidic solar-thermal energy harvesting under large-flux solar illumination. [Display omitted] [ABSTRACT FROM AUTHOR]

• We generate a stably self-dispersed crumpled graphene/water nanofluid at 100 °C. • The nanofluid enhances the heat transfer coefficient by 89.1% over deionized water. • The enhancement is due to the porous structure generated by self-assembly. Boiling can induce the self-assembly of nanomaterials in nanofluids to generate reliable micro/nanostructures for enhancing boiling heat transfer. The practical applications of most nanofluids in boiling, however, are limited by the poor thermal stability at the boiling point, and improving the thermal stability of nanofluids at such high temperature is challenging. Here, we demonstrate that the crumpled graphene can remain uniformly and stably dispersed within deionized water at the boiling point of 100 °C due to its highly wrinkled structure, while self-assembling to generate a porous structure on the substrate during boiling. Such porous structure can vary the surface micromorphology, wettability and roughness, which increases the nucleation sites and departure frequency of bubbles, thus effectively enhancing the critical heat flux and the maximum heat transfer coefficient by 80.7 and 89.1% compared to the pristine copper substrate, respectively. This in situ boiling-induced self-assembly provides a facile and low-cost strategy to achieve high-performance boiling heat transfer for a wide variety of nanomaterials. The crumpled graphene/water nanofluid used can be directly utilized as a phase change working medium in boiling systems to harvest thermal energy and generate clean steam. [Display omitted] [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome virus (PRRSV) is an important pathogen. Although tremendous effort has been made for the vaccine development, only modified live vaccines are widely used with arguably limited efficacy. Our previous study showed that the Fc-fused first four Ig-like domains of Sn (Sn4D-Fc) and the SRCR domains 5–9 of CD163 (SRCR59-Fc) can act as PRRSV soluble receptors (VSRs). In this study, we improved the VSR-based anti-PRRSV strategy by taming their Fc domains. Sequence alignment showed that the CH3 domain of pig IgG1 contained five putative amino acids involved in the interaction with the neonatal Fc receptor (FcRn). The M455L/N461S variant of SRCR59-Fc/Sn4D-Fc was created for the higher affinity of FcRn binding. Both rBac-SRCR59-lsFc/Sn4D-lsFc and rBac-SRCR59-Fc/Sn4D-Fc expressing the mutated or wild-type VSRs were generated for conceptual validation. Both immunofluorescence and Western blotting analysis showed that the two rBac vectors could express the encoded VSRs in cells with similar expression levels and anti-PRRSV effects. In the rBac-injected mice, the expression of SRCR59-lsFc/Sn4D-lsFc was significantly prolonged than that of SRCR59-Fc/Sn4D-Fc. Both plasma stability and serum half-life of the purified SRCR59-lsFc/Sn4D-lsFc were significantly improved than that of SRCR59-Fc/Sn4D-Fc. SRCR59-lsFc/Sn4D-lsFc-treated peripheral blood mononuclear cells showed significantly stronger cytotoxicity on PRRSV-infected primary alveolar macrophages than SRCR59-Fc/Sn4D-Fc-treated cells. For the first time, we demonstrated that both half-life and effector function of pig IgG Fc-fused proteins could be significantly improved by taming their CH3 domains. The rBac-SRCR59-lsFc/Sn4D-lsFc could be further developed as a novel anti-PRRSV reagent. • We engineered pig IgG CH3 domain for high affinity binding to FcRn. • We generated two rBacs expressing two different PRRSV soluble receptors. • We showed that engineering CH3 domain can significantly prolong half-lives of Fc-fused PRRSV soluble receptors. • We showed that engineering CH3 domain can significantly enhance cytotoxicity of Fc-fused PRRSV soluble receptors. [ABSTRACT FROM AUTHOR]

Direct absorption and conversion of sunlight by optical nanofluids into storable heat is an efficient and facile way to harness abundant clean solar energy, but achieving long-term stable dispersion of the nanofluids is challenging under elevated temperatures. Herein, we report the preparation of mesoporous crumpled graphene particles as self-dispersible solar absorbers that can achieve homogenous dispersion within medium-temperature silicone oil. The mesoporous crumpled graphene particles were synthesized by using an aerosol-assisted capillary compression process and a subsequent oxidative-etching reaction. By controlling the etching time, the introduced mesopores can tune the apparent density of the crumpled particles into a value comparable with the dispersing base fluid. The crumpled surface structure, small particle size and compatible density weaken the inter-particle van der Waals attraction and gravitational sedimentation tendency. The resultant silicone oil nanofluids have maintained their uniform dispersion under a heating temperature of 200 °C for 50 h. The stable uniform dispersion together with the high solar absorptance, the large specific heat capacity and the proper viscosity enabled the application of prepared nanofluids for consistent high-performance medium-temperature solar-thermal energy harvesting under concentrated solar irradiation. [Display omitted] • Mesopores are introduced to crumpled graphene particles to tailor the density. • Stable dispersion of mesoporous crumpled graphene particles in silicone oil is achieved. • The nanofluids have high solar absorptance, large heat capacity and suitable viscosity. • Medium-temperature nanofluidic solar-thermal energy harvesting is demonstrated. [ABSTRACT FROM AUTHOR]

Despite comprising much of the genome, transposons were once thought of as junk. However, transposons play many roles in the eukaryotic genome, such as providing new proteins as domesticated genes, expressing during germline-soma differentiation, function in DNA rearrangement in the offspring, and so on. We sought to describe the distribution and structural organization of the two autonomous transposons (ZB and PS) in the zebrafish genome and examine their expression patterns in embryos and adult tissues. The intact copy of ZB and PS was queried by BLAST on NCBI and ENSEMBL using default parameters. Of the copies with coverage and identity, more than 90 % were downloaded to do structural analysis. Spatial and temporal expression patterns were detected by qRT-PCR and Whole-mount in situ hybridization (WISH). There are 19 intact copies of ZB , encoding 341 amino acid residues with DD34E catalytic domain and flanked by 201bp TIRs, and seven intact PS copies, containing 425 amino acid residues with DD35D catalytic domain flanked by 28bp TIRs, were detected in the genome of zebrafish respectively. Analysis of genomic insertions indicated that both ZB and PS transposons are prone to be retained in the intron and intergenic regions of the zebrafish genome. The sense and antisense transcripts of ZB and PS were detected during embryonic development stages and exhibited similar expression patterns. The difference is that the sense strand transcript of ZB was explicitly expressed in midbrain-hindbrain boundary (MHB) and otic vesicle (OV), and pharyngeal arches and pharyngeal pouches (PA&PP) at 48 hpf. In adult zebrafish, the expressions of ZB and PS in muscle and brain are much higher than in other tissues. Our study results indicate that ZB and PS transposons may be involved in the embryonic development and regulation of somatic cells of certain adult tissues, such as the brain and muscle. [ABSTRACT FROM AUTHOR]

[Display omitted] • A W-Cu vapor chamber (VC) improves thermal management systems at high temperature. • A Cu coating layer enhances bonding strength with wick and isolates working medium. • The lateral thermal conductivity of W-Cu VC is ~1700 W/(m∙K) under 1.6 kW/cm2. • The W-Cu VC reduces the thermal stress at the interface between the VC and chip. The electronic industry is facing pressing needs for cooling system with high-performance in heat transfer and matched coefficient of thermal expansion (CTE) with the chips. Metal composite materials (MCMs) with low CTE can be used in cooling chips to overcome the thermal expansion mismatch between the cooling substrate and chips. However, low thermal conductivity of MCMs limits their application in electronic cooling systems. Increasing the percentage of components with high thermal conductivity can enhance the thermal conductivity of MCMs, but it often leads to increase CTE as well. Here, we demonstrate that vapor–liquid phase change can improve the heat transfer performance of tungsten-copper (W-Cu) alloy-based MCMs while maintain their low CTEs. Such strategy reduces the maximum temperature and thermal resistance of MCMs, and also allows for heat spreading from concentrated heat source with high power density. The W-Cu alloy-based vapor chamber (VC) has low thermal resistance of 0.38 K/W at 100 W and high lateral thermal conductivity of ~1727 W/(m·K). The W-Cu alloy-based VC can be readily integrated with the chip and heat sink to serve as cooling substrates for dissipating the heat and simultaneously lowering the thermal expansion mismatch by using its high thermal conductivity and low CTE. [ABSTRACT FROM AUTHOR]

• Erythritol is impregnated within surface-roughened hydrophilic copper foam. • Thermal conductivity and supercooling degree are simultaneously improved. • A latent-heat releasing percentage of 85.8% is achieved. • Medium-temperature solar-thermal energy harvesting is demonstrated. • Conversion of medium-temperature heat into usable electricity is demonstrated. Erythritol (ET) has received increasing research attention for medium-temperature phase change solar-thermal energy storage. However, ET suffers from serious supercooling, low thermal conductivity, poor solar absorption and leakage after melting, which lead to low solar-thermal energy harvesting and releasing efficiency. Herein, we simultaneously overcome these inherent shortcomings by impregnating ET within surface-roughened hydrophilic copper foam, which is prepared by subsequent oxidization of commercial copper foam and thermal reduction under hydrogen, and using stably dispersed crumpled graphene particles as the solar-thermal converter. Such oxidization-reduction-treated copper foam not only provides numerous heterogeneous nucleation sites and lowers the nucleation energy barrier for forming ET crystals during the solidification process, but also facilitates rapid charging and discharging along three-dimensional heat conductive networks, and confines the melted ET. Compared with neat ET, the copper foam-templated composites have reduced the supercooling degree by ~60 °C and improved thermal conductivity by more than 5 times, which in turn lead to a large latent-heat releasing percentage of 85.8% and a high heat-extraction efficiency of 94.2%. We demonstrate that such composites can be used for high-efficiency, medium-temperature, form-stable, direct solar-thermal energy harvesting, and the harvested heat can be readily converted into electricity to power small devices. [ABSTRACT FROM AUTHOR]