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Ethanolysis of lignite is an effective approach for converting organic matter of lignite to liquid coal derivatives. Xilinguole lignite (XL) was reacted with ethanol at 320 °C. Then ethanol and isometric carbon disulfide/acetone mixture were used to extract the reaction mixture in a modified Soxhlet extractor to afford extractable portion 1 (EP

Matrine (MT) is a major bioactive compound extracted from

The large library of organic dye molecules offers almost infinite possibilities for laser design, but still faces a great challenge in achieving pure dye aggregate lasers due to intermolecular quenching. Here, we report a kinetically controlled molecular self-assembly strategy to synthesize unconventional dye microcrystals for lasing. By increasing temperature, the dye self-assembly is transformed from thermodynamic to kinetic control. Unlike the thermodynamic microcrystal products incapable of lasing due to intermolecular charge-transfer-mediated excimer formation, the kinetic dye microcrystals have large intermolecular distances and weak intermolecular interactions, supporting highly efficient intramolecular charge-transfer monomer emission and low-threshold lasing. This work demonstrates single-crystal dye lasers, promising to unleash the full potential of laser dyes in solid-state lasers.

Owing to outstanding optoelectronic properties, halide perovskites are great candidates for novel laser display applications. However, the realization of their practical flat-panel display applications is challenging because of the incapacity to controllably assemble different halide perovskite microlaser arrays onto an identical substrate as pixelated full-color panels due to intrinsic fragile crystal lattices. Here, perovskite red-green-blue (RGB) microdisk arrays are reported, acting as flat-panels for full-color laser displays. A universal screen-overprinting technology is developed to integrate full-color perovskite microdisk arrays on a prepatterned template, which is on the basis of wet-solute-chemical dynamics involving a combination of surface tailoring and solvent selection. Via such an overprinting method, perovskite RGB microlaser matrices with precise localizations and well-defined dimensions were fabricated on an identical substrate, and each set of RGB microlaser served as a pixel for full-color display panels. On this basis, static and dynamic laser displays have been demonstrated with as-prepared full-color panels. These results will provide novel design concepts and device structures for future full-color laser display applications.

All-solid-state lithium-sulfur batteries (ASSLSBs) have become a promising candidate because of their high energy density and safety. To ensure the high utilization and electrochemical capacity of sulfur in all-solid-state batteries, both the electronic and ionic conductivities of the sulfur cathode should be as high as possible. In this work, an intercalation-conversion hybrid cathode is proposed by distributing sulfur evenly on electroactive niobium tungsten oxide (Nb

Porous organic materials (POMs) have shown great potential for fabricating tunable miniaturized lasers. However, most pure-POM micro/nanolasers are achieved via coordination interactions, during which strong charge exchanges inevitably destroy the intrinsic gain property and even lead to optical quenching, hindering their practical applications. Herein, we reported on an approach to realize hydrogen-bonded organic framework (HOF)-based

Serious lung diseases and other health problems caused by tobacco consumption are becoming more and more prominent all over the world. Scavenging the excessive harmful free radicals in cigarette smoke is proven to be an effective method in reducing the above problems. Carbon-based nanozymes have been widely studied due to their ability of scavenging free radicals. Accordingly, the biochar derived from silkworm excrement was reported as a nanozyme with free radical scavenging ability. The biochar nanozyme calcination at 900 °C with better free radical scavenging abilities was loaded into commercial cigarette filters for the following free radical scavenging verification in tobacco smoke. Mouse model results reveal the lung tissue could be improved by the addition of biochar nanozyme. This work not only provides an effective approach to reduce the harm caused by tobacco but also provides potential applications to rationally realize low-cost, ease of production, and a wide variety of biochar sources.

A type III polyketide synthase (SfuPKS1) from the edible seaweed Sargassum fusiforme was molecularly cloned and biochemically characterized. The recombinant SfuPKS1 catalyzed the condensation of fatty acyl-CoA with two or three malonyl-CoA using lactone-type intramolecular cyclization to produce tri- and/or tetraketides. Moreover, it can also utilize phenylpropanoyl-CoA to synthesize phloroglucinol derivatives through Claisen-type cyclization, exhibiting broad substrate and catalysis specificity. Furthermore, the catalytic efficiency (kcat/KM) for acetyl-CoA was 11.8-fold higher than that for 4-coumaroyl-CoA. A pathway for the synthesis of naringenin involving SfuPKS1 was also constructed in Escherichia coli by recombinant means, resulting in 4.9 mg of naringenin per liter.

Spider silk-inspired hydrogen-bond (H-bond) cross-linking has recently been shown to enable polymers, e.g., poly(vinyl alcohol) (PVA), to achieve high strength in combination with large ductility a...

Glass-ceramic sulfide solid electrolytes like Li7P3S11 are practicable propellants for safe and high-performance all-solid-state lithium-sulfur batteries (ASSLSBs); however, the stability and conductivity issues remain unsatisfactory. Herein, we propose a congener substitution strategy to optimize Li7P3S11 as Li7P2.9Sb0.1S10.75O0.25 via chemical bond and structure regulation. Specifically, Li7P2.9Sb0.1S10.75O0.25 is obtained by a Sb2O5 dopant to achieve partial Sb/P and O/S substitution. Benefiting from the strengthened oxysulfide structural unit of POS33- and P2OS64- with bridging oxygen atoms and a distorted lattice configuration of the Sb-S tetrahedron, the Li7P2.9Sb0.1S10.75O0.25 electrolyte exhibits prominent chemical stability and high ionic conductivity. Besides the improved air stability, the ionic conductivity of Li7P2.9Sb0.1S10.75O0.25 could reach 1.61 × 10-3 S cm-1 at room temperature with a wide electrochemical window of up to 5 V (vs Li/Li+), as well as good stability against Li and Li-In alloy anodes. Consequently, the ASSLSB with the Li7P2.9Sb0.1S10.75O0.25 electrolyte shows high discharge capacities of 1374.4 mAh g-1 (0.05C, 50th cycle) at room temperature and 1365.4 mAh g-1 (0.1C, 100th cycle) at 60 °C. The battery also presents remarkable rate performance (1158.3 mAh g-1 at 1C) and high Coulombic efficiency (>99.8%). This work provides a feasible technical route for fabricating ASSLSBs.

Solar selective absorber coatings (SSACs), with the characteristics of efficient harvesting and conversion of solar energy into the heat work fluid, are considered to be one of the key components f...

ConspectusIn the past decade, micro/nanoscale lasers have captured broad research interest for their feasibility in advancing the fields of photonics and optoelectronics. Owing to ease of spectral ...

Detecting conformational changes in protein is imperative due to its major role in neurodegenerative disorders. Here, we propose an alternative strategy for monitoring the structural change of proteins based on biological microlasers. Smart responsive protein-based microscale biolasers were constructed by incorporating organic gain medium into the microspheres of silk fibroin via emulsion-solvent evaporation. The lasing characteristic of the biolasers exhibited a sensitive response to the structural transformation of the silk fibroin. With narrowed linewidth, the as-prepared biolasers as sensing signals enable highly sensitive protein conformation detection. These results offer an effective approach to monitoring the protein conformational changes and provide valuable guidance for a better understanding of the relationship between bio-microstructures and their photonic properties.

Recent advances in high-entropy alloys have spurred many breakthroughs in the fields of high-temperature materials and optical materials and they provide incredible application potentialities for photothermal conversion systems. Solar-selective absorbers (SSAs), as key components, play a vital role in photothermal conversion efficiency and service life. The most pressing problem with SSAs is their inconsistent optical performance, an instability constraint induced by thermal stress. A feasible method of improving performance stability is the introduction of high-entropy materials, such as high-entropy alloy nitrides. In this study, enabled by an intrinsic MoTaTiCrN absorption layer, the solar configuration achieves greatly enhanced, exceptional thermotolerance and optical properties, leading to the formation of a scalable, highly efficient, and cost-effective structure. Computational and experimental approaches are employed to achieve optimum preparation parameters for thicknesses and constituents. The crystal structure of high-entropy ceramic MoTaTiCrN is fully investigated, including thickness-dependent crystal nucleation. High-temperature and long-term thermal stability tests demonstrate that our proposed SSA is mechanically robust and chemically stable. Moreover, a low thermal emittance (15.86%) at 500 °C promotes the photothermal conversion efficiency. In addition, due to the exceptional spectral selectivity (α/ε = 92.3/6.5%), thermal robustness (550 °C for 168 h), and photothermal conversion efficiency (86.9% at 550 °C under 100 sun), it is possible for our proposed SSA to enhance the practical realization of large-area photothermal conversion applications, especially for concentrated solar power systems.

We investigated the dynamics of the topological network formed by rotaxane-type movable crosslinks consisting of a poly(ethyl acrylate) backbone threaded through peracetylated cyclodextrins, which ...

Many functional polymeric materials are inherently fragile at ambient conditions. Making them elastic and flexible is a challenging task, and such achievement is especially meaningful in a wide ran...

Understanding the molecular composition of oxygen-containing aromatics (OCAs) in low-temperature coal tar (LTCT) is of great importance for separating value-added chemicals from LTCT and catalytica...

Single-ion conducting polymer electrolytes (SICPEs) have many advantages for solid-state battery applications, while low conductivities remain the bottleneck for their practical applications. Herei...

The development of simple and highly effective desulfurization technology is attracting more and more interest in both industrial and academic fields. Here, a new family of precursors was prepared based on hyper-cross-linked asphalt and coal tar building blocks. Thanks to the preintroduced porous structure, the precursors were converted into carbons with high surface area and large micropore volume via a uniform carbonization process. The synergistic effects of high surface area, abundant microporous structure, and the introduced polar functional groups endow the carbon materials with high desulfurization performance. The results of repeated experiments show that the adsorption capacities of five carbonized samples are higher than 40 mg S g-1, and the theoretical maximum adsorption capacity reaches 44.7 mg S g-1. Particularly, the adsorption equilibrium of all the carbonized samples can be reached in 5 min. Moreover, the recycle adsorption performance was also studied. Toluene exhibits the best elution effect among three eluents (iso-octane, para-xylene, and toluene) and the adsorption capacity remains 89% of the initial adsorption capacity after two adsorption-desorption cycles. It is believed that both innocent treatment of byproducts from petroleum industry and their high-value application for deep desulfurization in liquid hydrocarbon fuels benefit environmental protection and sustainable development.

There is an urgent need to discover new antibiotics and improve the efficacy of known antibiotics against Gram-negative bacteria. "Trojan horse" conjugates are novel and promising antibiotics. Herein we report the design and synthesis of vitamin-B12-ampicillin conjugates, which exhibited more than 500 times improved activity against Escherichia coli compared with ampicillin itself. Our studies demonstrate that the vitamin-B12 uptake pathway could be employed for effective antibiotic delivery and efficacy enhancement.

Ionic liquid (IL) properties, such as high ionic conductivity under ambient conditions combined with nontoxicity and nonflammability, make them important materials for future technologies. Despite high ion conductivity desired for battery applications, cation transport numbers in ILs are not sufficient enough to attain high power density batteries. Thus, developing novel approaches directed toward improvement of cation transport properties is required for the application of ILs in energy-storing devices. In this effort, we used various experimental techniques to demonstrate that the strategy of mixing ILs with ultrasmall (1.8 nm) nanoparticles (NPs) resulted in melt-processable composites with improved transport numbers for cations at room temperature. This significant enhancement in the transport number was attributed to the specific chemistry of NPs exhibiting a weaker cation and stronger anion coordination at ambient temperature. At high temperature, significantly weakened NP–anion associations promoted a liquid-like behavior of composites, highlighting the melt-processability of these composites. These results show that designing a reversible dynamic noncovalent NP–anion association controlled by the temperature may constitute an effective strategy to control ion diffusion. Our studies provide fundamental insights into mechanisms driving the charge transport and offer practical guidance for the design of melt-processable composites with an improved cation transport number under ambient conditions.

An efficient method for the synthesis of azabicyclo[5.1.0]octenes through cycloisomerization of nitrogen-tethered 1,7-enynes catalyzed by [IrCp*Cl2]2 was developed. With appropriately designed subs...

Nonclassical fullerene is a new member of the fullerene family. In the present work, a systematic investigation on LaxSc3–xN@C80 (x = 0–3) covering both classical and nonclassical C80 cages was per...

Fabrication of stretchable functional polymeric materials usually relies on the physical adhesion between functional components and elastic polymers, while the interfacial resistance is a potential...

Metal-organic frameworks (MOFs) are an emerging kind of laser material, yet they remain a challenge in the controlled fabrication of crystal nanostructures with desired morphology for tuning their optical microcavities. Herein, the shape-engineering of pure MOF microlasers was demonstrated based on the coordination-mode-tailored method. The one-dimensional (1D) microwires and 2D microplates were selectively fabricated through changing the HCl concentration to tailor the coordination modes. Both the single-crystalline microwires and microplates with strong optical confinement functioned as low-threshold MOF microlasers. Moreover, distinct lasing behaviors of 1D and 2D MOF microcrystals confirm a typical shape-dependent microcavity effect: 1D microwires serve as Fabry-Pérot (FP) resonators, and 2D microplates lead to the whispering-gallery-mode (WGM) microcavities. These results provide a special pathway for the exploitation of MOF-based micro/nanolasers with on-demand functions.

A palladium-catalyzed alkenylation involving remote δ-position C(alkenyl)–H activation of cycloalkenes reacting with electron-deficient alkenes is described. This method features excellent site selectivity and stereoselectivity to efficiently afford only E-selective highly substituted 1,3-diene derivatives with extra-ligand-free and good functional group tolerance including estrone and free N–H tryptamine under weakly alkaline conditions. Mechanistic studies suggest that picolinamide as a bidentate directing group enables the formation of unique alkenyl palladacycle intermediates.

Herein, we demonstrated a steric-hindrance-controlled laser switch in pure metal-organic framework (MOF) microcrystals. The well-faceted MOF microwires with aggregation-induced emission (AIE) lumnogens as linkers function as typical Fabry-Pérot microlasers. The steric hindrance around the AIE linkers can be reduced by the loss of guest molecules, which lead to the enhanced rotation of linkers with red-shifted gain behavior. On this basis, the gain region was readily switched through changing the steric hindrance via the desorption/adsorption of guests. As a result, the reversible switching of the dual-wavelength lasing from MOF microwires was achieved. The results provide a promising route to the development of versatile micro-/nanolasers with desired applications.

A method using aroyl chlorides as atom-transfer radical cyclization agents in a novel visible-light photocatalytic aroylchlorination reaction is developed. The overall transformation involves the formation of two new C-C bonds and one new C-Cl bond in a one-pot process. The advantages of this reaction include high atom/step/redox economy, mild conditions, operational simplicity, and broad substrate scopes.

Near-infrared (NIR) microlasers play a significant role in telecommunication and biomedical tissue imaging. However, it remains a big challenge to realize NIR microlasers because of the difficulty in preparing highly efficient NIR luminescent materials and perfect optical resonators. Here, we propose a molecular design strategy to creatively realize the first spiropyrane (SP)-based NIR microlasers with low threshold from self-assembled microsphercial caps. The tetraphenylethylene (TPE) moiety with a highly twisted conformation provides a large free volume to facilitate the photoisomerization process of SP and enhance NIR emission of merocyanine in the solid state. Moreover, self-assembled TPE-SP microsphercial caps simultaneously serve as gain media and resonant microcavities, providing optical gain and feedback for NIR laser oscillations with a low threshold (3.68 μJ/cm

[K(dibenzo-18-crown-6)]+ (KC) cations are used for cocrystallization with manganese halides, producing isostructural single crystals of organic–inorganic hybrid complexes, [K(dibenzo-18-crown-6)]2M...

An effective dual-solvent (DS) extraction combined with recrystallization was designed for refined paraffin (RP) separation from a shale oil (SO). The content of wax enriched with acetonitrile (AN)/petroleum ether is higher than that with other DSs. The maximum recovery of RP is 22.1 wt % obtained by regulating the DS/SO ratio, extraction time (ET), and extraction times (ETs). The corresponding total relative content of oil obtained by controlling solvent polarity during the recrystallization is 1.9% based on the analysis with a gas chromatograph/mass spectrometer. Long-chain n-alkanes are predominant in RPs, which is consistent with Fourier transform infrared analysis. In addition, the mechanisms for synergic DS extraction were revealed by quantum chemistry calculation with density functional theory, i.e., C–H···π and X–H···Y bonds exist between AN and selected model compounds according to the analyses of electrostatic potential and average local ionization energy. The low boiling point and immiscibility...

Thiol–ene chemistry draws much attention nowadays in the construction of functional polymer materials due to its versatility and fast reaction kinetics, though only a few studies have been reported...

Engineered nanoparticles (NPs) with activities that mimic antioxidant enzymes have good prospects in agriculture because they can increase photosynthesis and improve stress tolerance. Here, the interaction between cerium oxide NPs with spinach plants ( Spinacia oleracea) was investigated by integrating phenotypic and metabolomic analyses. Soil-grown, four-week-old spinach plants were foliar exposed for 3 weeks to CeO2 NPs at 0, 0.3, and 3 mg per plant. Phenotypic parameters (chlorophyll fluorescence, photosynthetic pigment contents, plant biomass, lipid peroxidation, and membrane permeability) were not affected. However, metabolomics analysis revealed that both doses of CeO2 NPs induced metabolic reprogramming in leaves and roots in a non-dose-dependent manner. The low dose of CeO2 NPs (0.3 mg per plant) induced stronger metabolic reprogramming in spinach leaves than high dose of CeO2 NPs. However, the high dose of CeO2 NPs triggered more metabolic changes in roots, compared to the low dose. Foliar spray of CeO2 NPs at 3 mg/plant induced marked down-regulation of a number of amino acids (threonine, tryptophan, l-cysteine, methionine, cycloleucine, aspartic acid, asparagine, tyrosine, and glutamic acid). In addition, Zn decreased by 44% and 54% in leaves and Ca decreased by 38% and 32% in roots under exposure to CeO2 NPs at 0.3 and 3 mg/plant, respectively. These results provide better understanding of the intrinsic phenotypic and metabolic changes imposed by CeO2 NPs in spinach plants.