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The close-in weapon system (CIWS) is a combat system that faces a complex environment full of dynamic and unknown challenges, whose construction and planning require a systematic design method. Multi-living agent (MLA) theory is a methodology for the combat system design, which uses the livelihood degree to evaluate the multi-dimensional long-term operational effectiveness of the system; whereas, there is still no uniform quantization framework for the livelihood degree, and the adjustment methods of livelihood degree need to be further improved. In this paper, we propose the uniform quantization framework for the livelihood degree and detailed discuss the methods of livelihood adjustment. Based on the MLA theory, the multi-dimensional operational effectiveness of the missile-gun integrated weapon system (MGIWS) is analyzed, and the long-term combat effectiveness against the saturation attack is assessed. Furthermore, the planning problem of the equipment deployment and configuration is investigated. Two objectives, including the overall livelihood degree and cost-effectiveness (CE), are proposed, and the optimization method based on genetic algorithm (GA) is studied for the planning problem.

Potassium-selenium (K-Se) batteries have attracted more and more attention because of their high theoretical specific capacity and natural abundance of K resources. However, dissolution of polyselenides, large volume expansion during cycling and low utilization of Se remain great challenges, leading to poor rate capability and cycle life. Herein, N/O dual-doped carbon nanofibers with interconnected micro/mesopores (MMCFs) are designed as hosts to manipulate Se molecular configuration for advanced flexible K-Se batteries. The micropores play a role in confining small Se molecule (Se2–3), which could inhibit the formation of polyselenides and work as physical barrier to stabilize the cycle performance. While the mesopores can confine long-chain Se (Se4–7), promising sufficient Se loading and contributing to higher discharge voltage of the whole Se@MMCFs composite. The N/O co-doping and the 3D interpenetrating nanostructure improve electrical conductivity and keep the structure integrity after cycling. The obtained Se2–3/Se4–7@MMCFs electrode exhibits an unprecedented cycle life (395 mA h g−1 at 1 A g−1 after 2000 cycles) and high specific energy density (400 Wh kg−1, nearly twice the specific energy density of the Se2–3@MMCFs). This study offers a rational design for the realization of a high energy density and long cycle life chalcogen cathode for energy storage.

A novel lightweight mullite fiber/phenolic ablator is readily fabricated using mullite fiber felt as the substrate and phenolic aerogel as the matrix via ambient pressure impregnation, sol-gel reaction and ambient pressure drying. The phenolic aerogel with a large amount of macropore can be well-embedded into the voids of flexible mullite fiber felt and form a superior interfacial interaction. The as-prepared mullite fiber/phenolic ablator has a low density of 0.30–0.33 g/cm3 and a relatively high bending strength of 3.4–13.6 MPa. Compared to conventional ablative materials, the mullite fiber/phenolic ablator shows a much lower thermal conductivity of 0.036–0.039 W/(m·K) at room temperature. Moreover, the obtained ablator with linear ablation rate as low as 0.031 mm/s, exhibits excellent ablation resistance and thermal insulation in oxyacetylene flame simulated high temperature of 2000 °C.

Three dimensional (3D) porous graphene can prevent restacking of graphene sheets and enables easy access and diffusion of ions, which affords possibility to fill the gap between laboratory research and industrialization of graphene. However, efficient synthesis of macroscopic thick 3D porous graphene films is still a challenge. Here, a novel strategy is firstly reported to straightforward synthesize 3D graphene, by high-energy e-beam induction on polyimide (PI). Due to high kinetic energy and low reflection features, energy of e-beam can be readily absorbed, leading to carbonization of PI and formation of macroscopic thick graphene films (0.66 mm) with abundant 3D pore structures and desirable electrical conductivity of 1100 S m−1. Meanwhile, the few-layer structure, low defects, high quality, and rapid synthesis speed (84 cm2 min−1), enable the as-obtained e-beam induced graphene (EIG) film to possess the potential for large-scale applications. Performances of EIG in energy storage and photothermal deicing have been explored. The EIG supercapacitor shows an impressive specific areal capacitance of 67.1 mF cm−2 at 0.1 mA cm−2. Besides, EIG exhibits desirable and eco-friendly photothermal deicing capability at −40 °C. This methodology exhibits wide applicability in pursuing concepts of fast, simple and low-cost for 3D graphene manufacturing and multidisciplinary applications.

Li-ion-conducting chloride solid electrolytes receive considerable attention due to their physicochemical characteristics such as high ionic conductivity, deformability and oxidative stability. However, the raw materials are expensive, and large-scale use of this class of inorganic superionic conductors seems unlikely. Here, a cost-effective chloride solid electrolyte, Li2ZrCl6, is reported. Its raw materials are several orders of magnitude cheaper than those for the state-of-the-art chloride solid electrolytes, but high ionic conductivity (0.81 mS cm–1 at room temperature), deformability, and compatibility with 4V-class cathodes are still simultaneously achieved in Li2ZrCl6. Moreover, Li2ZrCl6 demonstrates a humidity tolerance with no sign of moisture uptake or conductivity degradation after exposure to an atmosphere with 5% relative humidity. By combining Li2ZrCl6 with the Li-In anode and the single-crystal LiNi0.8Mn0.1Co0.1O2 cathode, we report a room-temperature all-solid-state cell with a stable specific capacity of about 150 mAh g–1 for 200 cycles at 200 mA g–1., Stable inorganic solid electrolytes are instrumental in developing high-voltage Li metal batteries. Here, the authors present the synthesis and electrochemical energy storage properties of a cost-effective and humidity-tolerant chloride solid electrolyte.

Solid electrolytes hold great promise for enabling the use of Li metal anodes. The main problem is that during cycling, Li can infiltrate along grain boundaries and cause short circuits, resulting in potentially catastrophic battery failure. At present, this phenomenon is not well understood. Here, through electron microscopy measurements on a representative system, Li7La3Zr2O12, we discover that Li infiltration in solid oxide electrolytes is strongly associated with local electronic band structure. About half of the Li7La3Zr2O12 grain boundaries were found to have a reduced bandgap, around 1–3 eV, making them potential channels for leakage current. Instead of combining with electrons at the cathode, Li+ ions are hence prematurely reduced by electrons at grain boundaries, forming local Li filaments. The eventual interconnection of these filaments results in a short circuit. Our discovery reveals that the grain-boundary electronic conductivity must be a primary concern for optimization in future solid-state battery design. Solid electrolytes are promising for enabling the use of Li metal anodes but Li infiltration along grain boundaries can lead to battery failure. Li infiltration in a model solid oxide electrolyte is now found to be strongly associated with local electronic band structure.

A rhodium-catalyzed dehydrogenative cycloisomerization of dienylcyclopropane compounds is reported, which provides a straightforward approach to a variety of highly substituted toluene derivatives in 67-85% yields. The dienylcyclopropane-imides are produced by a single-step formal three-component olefination procedure. Preliminary mechanistic studies indicated that an electron-withdrawing group as R plays a critical role in completing this transformation.

Developing an electrochemiluminescence (ECL) coreactant to minimize the biotoxicity and to maximize the enhancement factor is critical to single-cell ECL microscopy. Here, we reported a guanine-rich single-stranded DNA (G-ssDNA)-loaded high-index faceted gold nanoflower (Hi-AuNF) as a synergistic coreactant of Ru(bpy)32+ for single-cell ECL imaging. Because of the excellent catalytic performance and huge specific surface area, Hi-AuNF serves as not only an ECL enhancer but also a carrier for G-ssDNA. Guanine in G-ssDNA specifically reacts with Ru(bpy)32+ through a so-called "catalytic route" and thus significantly enhances the ECL signal of Ru(bpy)32+. To endow targeting ability to the synergistic coreactant, an aptamer of carcinoembryonic antigen (CEA) is incorporated into the G-ssDNA to form G-ssDNA-Apt for the recognition of human breast adenocarcinoma cells, which overexpress CEA on the cytomembrane. Accordingly, the ECL imaging of CEA on the cytomembrane was realized by using the highly selective Hi-AuNF@G-ssDNA-Apt as the probe as well as the luminophore of Ru(bpy)32+. Compared with the common coreactant tripropylamine with high toxicity and volatility, the Hi-AuNF@G-ssDNA-Apt is considered as a high-performance and biocompatible coreactant, providing exciting opportunities in single-cell imaging and detection.

The effect of microstructure evolution on the tensile properties of 2050 Al−Li alloy thick plate aged at 150 °C with 80 mm in thickness (t) was studied from a microstructural perspective. Scanning electron microscope, optical microscope, transmission electron microscope and X-ray diffractometer were used to explore the surface (t/6), interlayer (t/3) and center (t/2) thickness layer of this alloy. Results show that the secondary phases on grain boundaries, precipitates and textures vary depending on the thickness location. The precipitation strengthening has a stronger influence on the alloy along the rolling direction than the transverse direction from the under-aged to the peak-aging condition; however, its effect on the anisotropy is insignificant. The higher Taylor factor (M) value caused by stronger β fiber rolling textures and the intergranular phases is the main reason that leads to the highest strength at the t/2 position along the rolling direction. The M-value has a limited change at different thickness layers along the transverse direction, which causes the same tensile strength.

Interface instability that stems from highly catalytic Ni-rich layered cathode and highly reactive lithium metal anode is the key to hindering the development of high-voltage lithium metal batterie...

Lateral flow immunoassays (LFIs) can be used to detect intact bacteria or spores; when gold nanoparticles (AuNPs) are used as the signal reporters, the detection limits are very low. Spore-based surface display has been widely studied for enzyme immobilization and live-nontoxic oral vaccines. In this study, recombinant spores were used to improve the sensitivity of a LFI. We developed a test kit that combines streptavidin-displayed spores with a LFI assay for rapid protein detection. The recombinant spores served as a signal amplifier and AuNPs were used as the signal reporters. For detection of β-galactosidase, which was used as the model protein, the detection limit was about 10−15 mol, while that of the conventional LFI is about 10−12 mol. In both methods, nanogold was used as the colorimetric signal and could be observed with the naked eye. This method improved LFI sensitivity without sacrificing its advantages. Furthermore, enhanced green fluorescent protein (eGFP) was also displayed on the surface of the streptavidin-displayed spores. Without AuNPs, the fluorescent recombinant spores acted as the signal, which could be detected by a fluorescence detector, such as a fluorescence microscope. The detection limit was 10−16 mol under fluorescence microscopy whose magnification was 25-fold. Therefore, in conclusion, in this proof of concept study, the detection limits of both proposed methods were far superior to those of traditional LFI assay.

The interplay between solid electrolytes and electrodes is of vital importance to the performance of all-solid-state Li batteries. Recently, halide superionic conductors have emerged as a new family of high-performance solid electrolytes, but their compatibility with Li metal, i.e., the anode with the highest theoretical capacity, has not been systematically studied. Here, we investigate the interaction between Li metal and two representative halide solid electrolytes: Li3YCl6 and Li3YBr6. Both materials are found to form interphases with Li, similar to most solid electrolytes. However, the interphases observed here contain electronic conducting components, which are detrimental to their compatibility with Li. By elucidating this phenomenon, the present study provides guiding principles for improving the Li compatibility of halide solid electrolytes.

This paper presents a study of the influence of basalt rocks’ phase composition, acidity modulus, and structural parameter NBO/T on the tensile strength and elastic modulus of basalt continuous fibers (BCFs) derived from them. A series of BCF samples based on 14 different basalt deposits was obtained under equal conditions. The tensile strength and elastic modulus of the BCFs from different deposits vary in the ranges of 1495–3380 MPa and 58.2–78.7 GPa, respectively. Using the original method of quantitative phase analysis based on the Rietveld method, the phase compositions of the 14 deposits were defined. All deposits can be used to obtain BCFs. In the studied natural rocks, the main component is tectosilicates; the mass content of framework aluminosilicates is in the range of 16.5–3.3 mass percent. The second main component is inosilicates; the mass content of chain aluminosilicates is in the range of 6.0–58.0 mass percent. The correlations among phase composition, acidity modulus, ratio of non-bridging oxygens to tetrahedral cations, tensile strength, and elastic modulus of the BCFs from the 14 different basalt deposits were calculated. There were strong positive correlation between tectosilicate minerals mass content and elastic modulus [Pearson correlation coefficient (PCC) of 0.7] and strong negative correlation between content of chain and layered aluminosilicates and elastic modulus (PCC of − 0.74).

Hexavalent chromium is highly toxic and regarded as one of the main pollutants in the environment. Sophisticated laboratory instruments are commercially available for the in-field determination of chromium. It is highly desirable to develop affordable, portable, sensitive and reliable methods for on-site Cr(VI) detection. For field analysis, we designed a smartphone-based absorbance device with an ultralong absorption path to improve sensitivity. The intensity of the transmission light was detected by the illumination sensor in the smartphone. The absorption path was enlarged to a maximum of 83.5 cm by 41 reflection cycles. The intensity of the reflected light in an empty colorimetric cell can be serviced as the internal references to correct the possible baseline drift due to light source intensity decay. The absorbance measured by the proposed device obeys the Lambert–Beer law in the range of 0–1.1. This device was used to determine Cr(VI) in water samples on-site by using 1,5-diphenylcarbazide as a colorimetric reagent, with the linear range of 1–18 μg L−1 and limit of detection of 0.26 μg L−1. This simple absorbance device offers the advantages of cost-effectiveness, ease of implementation, portability, sensitivity and reliability for field analysis.

A cocktail [1 + 2] dual-fluorescent probe system was developed to realize the real-time visualization of dynamic iron state changes between Fe2+ and Fe3+ at the cellular level and in multicellular organisms, providing insights into the effect of DMT1 and ferroportin on iron regulation.

Objectives Subbranches of Y-chromosome haplogroup C2a-L1373 are founding paternal lineages in northern Asia and Native American populations. Our objective was to investigate C2a-L1373 differentiation in northern Asia and its implications for Native American origins. Materials and methods Sequences of rare subbranches (n = 43) and ancient individuals (n = 37) of C2a-L1373 (including P39 and MPB373), were used to construct phylogenetic trees with age estimation by BEAST software. Results C2a-L1373 expanded rapidly approximately 17.7,000-14.3,000 years ago (kya) after the last glacial maximum (LGM), generating numerous sublineages which became founding paternal lineages of modern northern Asian and Native American populations (C2a-P39 and C2a-MPB373). The divergence pattern supports possible initiation of differentiation in low latitude regions of northern Asia and northward diffusion after the LGM. There is a substantial gap between the divergence times of C2a-MPB373 (approximately 22.4 or 17.7 kya) and C2a-P39 (approximately 14.3 kya), indicating two possible migration waves. Discussion We discussed the decreasing time interval of "Beringian standstill" (2.5 ky or smaller) and its reduced significance. We also discussed the multiple possibilities for the peopling of the Americas: the "Long-term Beringian standstill model," the "Short-term Beringian standstill model," and the "Multiple waves of migration model." Our results support the argument from ancient DNA analyses that the direct ancestor group of Native Americans is an admixture of "Ancient Northern Siberians" and Paleolithic communities from the Amur region, which appeared during the post-LGM era, rather than ancient populations in greater Beringia, or an adjacent region, before the LGM.

Lithium-sulfur (Li-S) batteries are considered as a promising candidate of next generation lithium batteries by virtue of high theoretical energy density, low cost and eco-friendliness, yet their commercialization still suffers from undesirable polysulfide shuttling and uncontrollable Li dendrites growth. Herein, a dual-engineered separator is designed through double-side construction of ammonium alcohol polyvinyl phosphate/carbon black (AAPP/CB) constituted “polysulfide stockroom” and Li1.5Al0.5Ge1.5(PO4)3 (LAGP) based “ion guider” on a commercial polypropylene (PP) substrate. Such functional separator AAPP/CB@PP@LAGP enables highly robust, all-climate Li-S batteries, which is attributed to the efficient polysulfide-absorption/conversion function of the AAPP/CB layer and uniform Li ion distribution/transport capacity induced by the LAGP layer. It is anticipated that this work may provide a promising strategy for interface engineering of separators and promote the wide-temperature application of Li-S batteries.

This paper reported the preparation of a hierarchical structure consisting of micro-scale basalt fiber fabric and nano-scale carbon nanotubes (CNTs). The developed fabric was employed as reinforcement to develop nanocomposites with multi-layer structures for electromagnetic interference shielding. Different techniques were employed to study the morphologies and properties of the fabric and corresponding nanocomposites. The results showed that by optimizing the experimental conditions, CNTs with controlled content and quality were grown on the surface of basalt fiber. These properties significantly affected the electromagnetic interference shielding performance of corresponding nanocomposites. The novelty of this study lies in the direct growth of nanotubes on basalt fiber by utilizing the in-situ generated mineral nanoparticles on fiber surface as a catalyst, and a spontaneous infusion of uncured polymer into the fabric, which eliminates the problems associated with the dispersion and re-agglomeration of CNTs during the preparation of nanocomposites.

Detection of protein-binding analytes is important for many applications. Currently, various instrument-based techniques are used for detecting protein-binding analytes. However, such techniques have several limitations including high cost and time-consuming sample processing. In order to overcome these limitations, we developed a sensitive competition assay for the detection of protein-binding analytes using recombinant endospores as a sensing element. The method is based on the competition between the biotin, the model analyte, and a biotin-magnetic bead complex to bind the recombinant spores containing the biotin binding region of streptavidin. After magnetic attraction, the residual spores in the suspension are spread on plates to form colonies which are used to count the amount of the residual spores; the higher the residual ratio of spores, the more biotin in the samples. The linear range was from 150 zmol to 1.5 fmol and the limit of detection of the assay was 150 zmol. The assay proposed herein is sensitive and does not require any expensive equipment. It is suitable for qualitative or semi-quantitative analysis such as screening tests for the detection of toxic chemicals.

Li-stuffed garnet oxides are one of the most promising solid electrolytes for Li batteries, but their development is impeded by the overly high sintering temperature (above 1000 °C), which causes uncontrollable Li evaporation and poor repeatability of synthesis. The present study evaluates the possibility of addressing this issue using a recently developed technique called cold sintering process (CSP). We demonstrates that CSP can easily realize a high density of 87.7% at an extremely low temperature of 350 °C. However, the material becomes air sensitive after CSP, and the conductivity is degraded. Detailed structural and chemical analyses reveal that such detrimental effects arise from the inter-granular phase induced by the preferential dissolution of Al and Li. Therefore, in order to take full advantage of CSP during solid-electrolyte fabrication, the incongruent dissolution issue must be the focal point of improvement. Our results suggest that CSP is a promising solution to the overly high sintering temperature of garnet electrolytes, and deserves more attention in future studies.

The sluggish kinetics of lithium polysulfides (LiPS) transformation is recognized as the main obstacle against the practical applications of the lithium-sulfur (Li-S) battery. Inspired by molybdoenzymes in biological catalysis with stable Mo-S bonds, porous Mo-N-C nanosheets with atomically dispersed Mo-N2/C sites are developed as a S cathode to boost the LiPS adsorption and conversion for Li-S batteries. Thanks to its high intrinsic activity and the Mo-N2/C coordination structure, the rate capability and cycling stability of S/Mo-N-C are greatly improved compared with S/N-C due to the accelerated kinetics and suppressed shuttle effect. The S/Mo-N-C delivers a high reversible capacity of 743.9 mAh g-1 at 5 C rate and an extremely low capacity decay rate of 0.018% per cycle after 550 cycles at 2 C rate, outperforming most of the reported cathode materials. Density functional theory calculations suggest that the Mo-N2/C sites can bifunctionally lower the activation energy for Li2S4 to Li2S conversion and the decomposition barrier of Li2S, accounting for its inherently high activity toward LiPS transformation.

Ni0.5Zn0.5Fe2−xCrxO4 (0≤x≤0.5) ferrites were successfully prepared by conventional solid state reaction method to investigate the effect of chromium substitution on the structural, electrical and magnetic properties. X-ray powder diffraction results demonstrate that all the prepared samples are well crystallized single-phase spinel structures without secondary phase. As chromium concentration increases, the lattice parameter and crystallite size gradually decrease. The magnetic measurement indicates that saturation magnetization is substantially suppressed by Cr3+ doping, changing from 73.5 A·m2/kg at x=0 to 46.3 A·m2/kg at x=0.5. While the room-temperature electrical resistivity is more than four orders of magnitude enhanced by Cr3+ substitution, reaching up to 1.1×108 Ω·cm at x=0.5. The dielectric constant monotonously decreases with rising frequency for these ferrites, showing a normal dielectric dispersion behavior. The compositional dependence of dielectric constant is inverse with that of electrical resistivity, which originates from the reduced Fe2+/Fe3+ electric dipole number by doping, indicating inherent correlation between polarization and conduction mechanism in ferrite.

Objective To isolate the phenolic compounds obtained from the dried roots of Polygonum multiflorum and investigate their pharmacological activities. Methods The chemical constituents were isolated and purified by combining them with a macroporous resin (DM-8), MCI gel, and Sephadex LH-20 and by performing ODS column chromatography. Their structures were elucidated by 1D and 2D NMR analyses, as well as mass spectrometry. The isolated compounds were evaluated to determine their hepatoprotective and α-glucosidase inhibitory activities in vitro. Results Two phenolic compounds, namely, polygonimitin E (1) and polygonimitin F (2), were isolated from the dried roots of P. multiflorum. Compound 2 (10 µmol/L) only showed moderate hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced HepG2 cell damage. Unfortunately, these two compounds exhibited no α-glucosidase inhibitory activity. Conclusion Compounds 1 and 2 were new compounds. Compound 2 could be one of the potential hepatoprotective constituents of P. multiflorum.

Sizing, a liquid mixture consisting of film former, coupling agent, antistatic and lubricant agents, is normally applied onto the surface of basalt fiber (BF) immediately after the filament was dra...

Few studies reported the extent of heavy metal accumulation in traditional Chinese medicines (TCMs). Currently, oral bioaccessibility of lead (Pb), cadmium (Cd), arsenic (As), mercury (Hg), and copper (Cu) present in traditional animal medicines was investigated with physiologically based extraction test-extracted in vitro model. We are the first to develop a health risk assessment strategy by combinational analysis of bioaccessible heavy metal levels to calculate target hazard quotient (THQ), target hazard index (THI) and cancer risk (CR), which has capacity to evaluate the heavy metal associated heath risk of traditional animal medicines. To precisely acquire a realistic risk assessment, questionnaire data was adopted to measure the frequency and duration of the exposure to traditional animal medicines, and the safety factor was highlighted as well. Our data revealed that the bioaccessibility of Hg was the lowest among the five heavy metals. After the adjustment with the bioaccessibility of each heavy metal to target hazard index (THI) values, excitingly, the results manifested that the consumption of traditional animal medicines might not exert an unacceptable health risk in a broad community. In addition, the CR values of As and Pb indicated that the risk of developing cancers was quite lower than their acceptable levels in the clinic.

The microstructure evolution and the corrosion feature of Al–xCu–yLi–Mg alloys (x:y = 0.44, 1.65 and 4.2) were systematically investigated under the same artificial aging conditions. The relationships between types of precipitates and mechanical performance, as well as electrochemical behaviors, were discussed. Our results show that different types of precipitates can be obtained in alloys with different Cu/Li mass ratios, which significantly influences the mechanical performance of the alloys and substantial corrosion behaviors. Specifically, the analogous corrosion evolution in the aging Al–xCu–yLi–Mg alloys was first ascertained to be derived from the growth mechanism of the precipitates at the grain boundary (GB). Moreover, a small number of GB precipitates can be obtained in the aged alloy with the lowest Cu/Li mass ratio, thereby resulting in the largest intergranular corrosion resistance. A higher proportion of the GB T1 phase in the continuous precipitates induces higher corrosion sensitivity in alloy with a high Cu/Li mass ratio.

Stress corrosion cracking (SCC) of an SA508-309 L/308 L–316 L dissimilar metal weld joint in primary pressurized water reactor environment was investigated by the interrupted slow strain rate tension tests following a microstructure characterization. The 308 L weld metal shows a higher content of δ ferrite than the 309 L weld metal. In addition, no obvious Cr-depletion but carbides precipitation at γ/δ phase boundaries was observed in both 308 L and 309 L weld metals. The slow strain rate tension tests showed that the SCC susceptibility of the base and weld metals of the dissimilar metal weld joint follows the order of SA508

Lead halide perovskites have been promising electrochemiluminescence (ECL) candidates because of their excellent photophysical attributes, but their poor stability has severely restricted ECL applications. Herein, the in situ assembly of all-inorganic perovskite CsPbBr3 nanocrystals (CPB) into hollow graphitic carbon nitride nanospheres (HCNS) were described as a novel ECL emitter. The architecture guaranteed not only improved stability because of the peripheral HCNS protecting shell but also high-performance ECL of CPB because of a matching band-edge arrangement. Dual-ECL readouts were obtained from the nanocomposite including an anodic ECL from CPB and a cathodic ECL from HCNS. The former displayed prominent color purity to construct an efficient ECL resonance energy transfer system, and the latter served as an internal standard for a ratiometric analysis. A well-designed DNA probe was further utilized for the targeting of CD44 receptors on the MCF-7 cell surface and the double signal amplification. The sensing strategy exhibited good analytical performance for MCF-7 cells, ranging from 1.0 × 103 to 3.2 × 105 cells mL-1 with a detection limit of 320 cells mL-1. Sensitive and accurate evaluation of CD44 expression was finally achieved at 0.22 pM. This work is the first attempt to use halide perovskite for reliable ECL bioanalysis and provides a perspective to design a perovskite-based nanocomposite as a high-performance ECL emitter for its exclusive ECL system.

Highly luminescent inks are desirable for various applications such as decorative coating, art painting, and anticounterfeiting, to name a few. However, present inks display low photoluminescent efficiency requiring a strong excitation light to make them glow. Here, we report a highly luminescent ink based on the copper-iodide/1-Propyl-1,4-diazabicyclo[2.2.2]octan-1-ium (Cu4I6(pr-ted)2) hybrid cluster with a quantum efficiency exceeding 98%. Under the interaction between the Cu4I6(pr-ted)2 hybrid cluster and polyvinylpyrrolidone (PVP), the highly luminescent Cu4I6(pr-ted)2/PVP ink can be facilely prepared via the one-pot solution synthesis. The obtained ink exhibits strong green light emission that originates from the efficient phosphorescence of Cu4I6(pr-ted)2 nanocrystals. Attractively, the ink displays high conversion efficiency for the ultraviolet light to bright green light emission due to its wide Stokes shift, implying great potential for anticounterfeiting and luminescent solar concentrator coating.

Cyclodextrins (CDs) had been regarded as destructors in molecular assembly systems for a long time until CD/surfactants were found to assemble into high order structure driven by hydrogen bonding between CDs. Thereafter, intensive researches have been conducted on construction and regulation of CD–amphiphile systems. Here, we summarized the recent progress on construction and regulation of CDs and amphiphiles assembly. The scope of amphiphiles have been extended from surfactants (ionic surfactants, zwitterion surfactants, nonionic surfactants, gemini surfactant, and so on), to nontypical amphiphiles (amines, aromatic molecules, alkanes, and so on). Owing to the abundant choices of guest amphiphiles and dynamic nature of host–guest inclusive interaction, numerous regulation methods (such as enzyme, light, pH, concentration, temperature, and so on) have been used in CD–amphiphile systems. Moreover, remarks and future perspectives are also discussed at the end of this review, which is expected to stimulate progress on both mechanism and application level.

Many platinum group metal-free inorganic catalysts have demonstrated high intrinsic activity for diverse important electrode reactions, but their practical use often suffers from undesirable structural degradation and hence poor stability, especially in acidic media. We report here an alkali-heating synthesis to achieve phase-mixed cobalt diselenide material with nearly homogeneous distribution of cubic and orthorhombic phases. Using water electroreduction as a model reaction, we observe that the phase-mixed cobalt diselenide reaches the current density of 10 milliamperes per square centimeter at overpotential of mere 124 millivolts in acidic electrolyte. The catalyst shows no sign of deactivation after more than 400 h of continuous operation and the polarization curve is well retained after 50,000 potential cycles. Experimental and computational investigations uncover a boosted covalency between Co and Se atoms resulting from the phase mixture, which substantially enhances the lattice robustness and thereby the material stability. The findings provide promising design strategy for long-lived catalysts in acid through crystal phase engineering., Noble-metal-free catalysts often show stability issues in acidic media due to structural degradation. Here authors show that phase-mixed engineering of cobalt diselenide electrocatalysts can enable greater covalency of Co-Se bonds and improve robustness for catalyzing hydrogen evolution in acid.

It still requires further investigations on the status of iron-based compounds and actual active sites in iron and nitrogen modified carbon based oxygen reduction catalysts (Fe N C), even though Fe-Nx groups have been confirmed as a type of dominating active site for most Fe N C systems. Herein, a facile and practical surface engineering process is adopted to transform metallic iron and iron trioxide nanoparticles into Fe2N nanocrystals, meanwhile to make their coated graphitic carbon shells interrupted and broken. This sufficiently facilitates the elimination of embedded Fe2N with a subsequent acid-etching process, eventually obtaining AA-Fe2N@NC sample. Based on various physicochemical characterizations, it is found that the relative concentrations of defective carbon and pyridinic N for AA-Fe2N@NC are clearly enhanced, compared to its counterpart (Fe2N@NC sample). Electrochemical measurements demonstrate that AA-Fe2N@NC instead of Fe2N@NC has optimal onset potential (72 mV positive shift), half-wave potential (45 mV positive shift) and limiting current density values (increased by 0.97 mA cm−2). When used as an air cathode of rechargeable Zn-air battery, it delivers a high power density of 168.15 mW cm−2, meanwhile a long-life cycling durability (60 h operation with an increased voltage gap of only 70 mV) is realized at 5 mA cm−2. Combined with the calculation of TOF values and SCN- inhibition test, we make a conclusion and highlight that, in alkaline electrolyte, carbon defects and pyridinic N for this Fe N C system rather than Fe2N compounds or Fe-Nx groups actually serve as the dominant active sites to afford a high-performance output of ORR activity.

Mesoporous carbon microspheres (MCMs) were prepared via a spray drying-assisted template method using resorcinol-formaldehyde as the carbon precursor and water glass as the template. The pore structure could be controlled by adjusting the hydrolysis time, hydrolysis temperature, concentration of the water glass and reactant ratio. Water glass could be recycled after use, making this strategy environmentally friendly and cost-effective. MCMs with three-dimensional interconnected networks, high surface area (852–1549 m2 g−1), large pore volume (1.7–2.1 cm3 g−1) and controllable pore diameter (3.8–15.1 nm) were constructed and have good electrical conductivity and a large volume for sulfur loading. The S/MCM composites with abundant residual nanochannels could not only benefit for the diffusion of electrolyte but also improve the utilization of sulfur and buffer the volume expansion of sulfur. The MCMs with relatively small mesopores manifest a high reversible capacity and rate performance owing to the strong confinement effect of polysulfides. MCM-1 delivered an initial capacity of 888.7 mA h g−1 under 0.5C with a capacity retention of 700.5 mA h g−1 after 100 cycles. The good electrochemical performance confirms that mesoporous carbon microspheres can be an excellent host material for sulfur cathodes.

In the past decade, flexible physical sensors have attracted great attention due to their wide applications in many emerging areas including health-monitoring, human-machine interfaces, smart robots, and entertainment. However, conventional sensors are typically designed to respond to a specific stimulus or a deformation along only one single axis, while directional tracking and accurate monitoring of complex multi-axis stimuli is more critical in practical applications. Multidimensional sensors with distinguishable signals for simultaneous detection of complex postures and movements in multiple directions are highly demanded for the development of wearable electronics. Recently, many efforts have been devoted to the design and fabrication of multidimensional sensors that are capable of distinguishing stimuli from different directions accurately. Benefiting from their unique decoupling mechanisms, anisotropic architectures have been proved to be promising structures for multidimensional sensing. This review summarizes the present state and advances of the design and preparation strategies for fabricating multidimensional sensors based on anisotropic conducting networks. The fabrication strategies of different anisotropic structures, the working mechanism of various types of multidimensional sensing and their corresponding unique applications are presented and discussed. The potential challenges faced by multidimensional sensors are revealed to provide an insightful outlook for the future development.

The dried root of Isatis tinctoria L. (Brassicaceae) is one of the most popular traditional Chinese medicines with well-recognized prevention and treatment effects against viral infections. Above 300 components have been isolated from this herb, but their spatial distribution in the root tissue remains unknown. In recent years, mass spectrometry imaging (MSI) has become a booming technology for capturing the spatial accumulation and localization of molecules in fresh plants, animal, or human tissues. However, few studies were conducted on the dried herbal materials due to the obstacles in cryosectioning. In this study, distribution of phytochemicals in the dried root of Isatis tinctoria was revealed by microscopic mass spectrometry imaging, with application of atmospheric pressure–matrix-assisted laser desorption/ionization (AP-MALDI) and ion trap–time-of-flight mass spectrometry (IT-TOF/MS). After optimization of the slice preparation and matrix application, 118 ions were identified without extraction and isolation, and the locations of some metabolites in the dried root of Isatis tinctoria were comprehensively visualized for the first time. Combining with partial least square (PLS) regression, samples collected from four habitats were differentiated unambiguously based on their mass spectrometry imaging.

Ultrasound and photoacoustic imaging are emerging as powerful tools to study brain structures and functions. The skull introduces significant distortion and attenuation of the ultrasound signals deteriorating image quality. For biological studies employing rodents, craniotomy is often times performed to enhance image qualities. However, craniotomy is unsuitable for longitudinal studies, where a long-term cranial window is needed to prevent repeated surgeries. Here, we propose a mouse model to eliminate sound blockage by the top portion of the skull, while minimum physiological perturbation to the imaged object is incurred. With the new mouse model, no craniotomy is needed before each imaging experiment. The effectiveness of our method was confirmed by three imaging systems: photoacoustic computed tomography, ultrasound imaging, and photoacoustic mesoscopy. Functional photoacoustic imaging of the mouse brain hemodynamics was also conducted. We expect new applications to be enabled by the new mouse model for photoacoustic and ultrasound imaging.

Tropospheric ozone in the surface air has become the primary atmospheric pollutant in Hangzhou, China, in recent years. Previous analysis is not enough to decode it for better regulation. Therefore, we use the traditional atmospheric model, Weather Research and Forecasting coupled with Community Multi-scale Air Quality (WRF-CMAQ), and machine learning models, Extreme Learning Machine (ELM), Multi-layer Perceptron (MLP), Random Forest (RF) and Recurrent Neural Network (RNN) to analyze and predict the ozone in the surface air in Hangzhou, China, using meteorology and air pollutants as input. We firstly quantitatively demonstrate that the dew-point deficit, instead of temperature and relative humidity, is the predominant meteorological factor in shaping tropospheric ozone. Urban heat island, daily direct solar radiation time, wind speed and wind direction play trivial role in impacting tropospheric ozone. NO2 is the primary influential factors both for hourly ozone and daily O3-8 h due to the titration effect. The most environmental-friendly way to mitigate the ozone pollution is to lower the volatile organic compounds (VOCs) with the highest ozone formation potentials. We deduce that the tropospheric ozone formation process tends to be not only non-linear but also non-smooth. Compared with the traditional atmospheric models, machine learning, whose characteristics are rapid convergence, short calculating time, adaptation of forecasting episodes, small program memory, higher accuracy and less cost, is able to predict tropospheric ozone more accurately.

Two-dimensional (2D) superlattices offer promising technological opportunities in tuning the intercalation chemistry of metal ions. Now, well-ordered 2D superlattices of monolayer titania and carbon with tunable interlayer-spacing are synthesized by a molecularly mediated thermally induced approach. The 2D superlattices are vertically encapsulated in hollow carbon nanospheres, which are embedded with TiO2 quantum dots, forming a 0D-2D-3D multi-dimensional architecture. The multi-dimensional architecture with the 2D superlattices encapsulated inside exhibits a near zero-strain characteristic and enriched electrochemical reactivity, achieving a highly efficient Na+ storage performance with exceptional rate capability and superior long-term cyclability.

Materials with controlled surface properties show great potential for various applications. In this paper, we reported a method to prepare a superhydrophilic fabric consisting of basalt fibre (BF) and konjac glucomannan (KGM). Different techniques were employed to study the morphology and surface information of the developed materials. The results showed that the KGM was deacetylated to form a hydrogel when processed in an alkali condition, and the excellent film-forming performance of the hydrogel led to the formation of a coating layer on BF fabric. The coating endowed the developed fabric with enhanced mechanical performance and superhydrophilicity in air condition. Interestingly, the material, subjected to a water condition, exhibited a stable superoleophobicity as confirmed by the extremely low adhesion to oil and remarkable resistance to the corrosive liquids, thus holding the promise to be a suitable candidate for separating various oil-water mixtures.

There are two general approaches to developing artificial general intelligence (AGI)1: computer-science-oriented and neuroscience-oriented. Because of the fundamental differences in their formulations and coding schemes, these two approaches rely on distinct and incompatible platforms2–8, retarding the development of AGI. A general platform that could support the prevailing computer-science-based artificial neural networks as well as neuroscience-inspired models and algorithms is highly desirable. Here we present the Tianjic chip, which integrates the two approaches to provide a hybrid, synergistic platform. The Tianjic chip adopts a many-core architecture, reconfigurable building blocks and a streamlined dataflow with hybrid coding schemes, and can not only accommodate computer-science-based machine-learning algorithms, but also easily implement brain-inspired circuits and several coding schemes. Using just one chip, we demonstrate the simultaneous processing of versatile algorithms and models in an unmanned bicycle system, realizing real-time object detection, tracking, voice control, obstacle avoidance and balance control. Our study is expected to stimulate AGI development by paving the way to more generalized hardware platforms. The ‘Tianjic’ hybrid electronic chip combines neuroscience-oriented and computer-science-oriented approaches to artificial general intelligence, demonstrated by controlling an unmanned bicycle.

Seeking of novel materials with special wettability is highly demanded for efficient separation of emulsified mixtures. In this study, carbonized melamine foam modified with cobalt hydroxide nanosheets was fabricated by a two-step route consisting of thermal pyrolysis and controlled chemical precipitation. The developed material exhibited a superamphiphilicity in air, and a controlled superoleophobic or superhydrophobic performance in various liquid conditions. By utilizing these properties, the composite foam was used as a bi-functional material to separate various oil-water emulsions. The results demonstrated that the developed material, solely using gravity without external stimulus, had the capability to separate not only the surfactant-stabilized oil-in-water emulsions with a high separation flux, but also the water-in-oil ones with remarkable oil purity. The facile method for the material preparation, high separation merit and excellent anti-fouling property of material provided a new candidate for the separation of emulsion systems.

MnCO3-based materials with high electrochemical activity and good structural stability hold great potential as advanced anode materials for lithium-ion batteries (LIBs). However, the poor Li+/e− conductivities and large volume changes during the charge/discharge process greatly hinder the application of MnCO3. In this work, the ingenious 3D architecture of graphene-wrapped porous MnCO3 microspheres is well designed and constructed via a facile and low-cost process without any structure-directing agents nor surfactants. The composites exhibit superior lithium storage capacity (1168 mA h g−1 after 200 cycles at 500 mA g−1) and ultra-long cycling life (595 mA h g−1 after 1000 cycles at high rate of 3000 mA g−1). The results obtained from the systematic electrochemical study demonstrate that the introduction of graphene could not only buffer the volume expansion of MnCO3 and ensure the rapid transportation of Li+/e−, but also improve the interfacial lithium storage property by enhancing surface capacitive contribution. Furthermore, full cells with the composite as anodes and commercial LiNi0.5Co0.2Mn0.3O2 as cathodes are assembled, which show good cycling stability, suggesting excellent practical adaptability of the composite anodes. This work provides a methodology to design and create composite anodes which could be extended to the synthesis of other graphene coated metal carbonates for lithium-ion batteries.

In this study, probe/primers of high specificity and sensitivity were selected to analyze donkey-hide gelatin for donkey DNA and to look for horse, ox, and pig DNA as possible adulterants. The mitochondrial CO I genes in donkey, horse, and ox were selected as target sequences for design and synthesis of three pairs of specific probes and primers. In addition, eight pairs of probe/primers were obtained via literature search. Out of these eleven groups of probe/primers, those with the highest specificity and sensitivity were selected, which was fulfilled by the screening firstly with animal hide samples then the hide-glue samples. Other parameters that might affect detection specificity and efficiency-such as the amount of sampling and final concentration of primers-were also optimized. Replication tests were also conducted. The results showed that the selected probe/primers could accurately detect donkey DNA and horse, ox, and pig DNA in gelatin samples with good reproducibility. Analysis of four samples of on-market gelatin using this assay showed that two of the four samples indeed contained only donkey DNA, whereas the other two samples contained both donkey and horse DNA, indicating adulteration of these samples with horse hide. These results indicate that the TaqMan probe real-time PCR method can be used for identifying the purity of donkey DNA in gelatin samples, and can provide technical support for identifying adulterations in the gelatin market.

In this work, a potential-resolved electrochemiluminescence (ECL) method is developed and used for the apoptosis diagnosis at the single-cell level. The apoptosis of cells usually induces the decreasing expression of epidermal growth factor receptor (EGFR) and promotes phosphatidylserine (PS) eversion on the cell membrane. Here, Au@L012 and g-C3N4 as ECL probes are functionalized with epidermal growth factor (EGF) and peptide (PSBP) to recognize the EGFR and PS on the cell surface, respectively, showing two well-separated ECL signals during a potential scanning. Experimental results reveal that the relative ECL change of g-C3N4 and Au@L012 correlates with the degree of apoptosis, which provides an accurate way to investigate apoptosis without interference that solely changes EGFR or PS. With a homemade ECL microscopy, we simultaneously evaluate the EGFR and PS expression of abundant individual cells and, therefore, achieve the visualization analysis of the apoptosis rate for normal and cancer cell samples...

Licorice, one of the oldest traditional Chinese medications, is widely used in the treatment of various diseases. With the development of science and technology, an increasing amount of analytical ...

The ability to modulate the phase behavior of an aqueous surfactant two-phase (ASTP) system reversibly with light is of great importance in both fundamental and applied science. Thus far, most of the light-responsive ASTP systems are based on covalent modification of the component molecules. In this article, we, for the first time, achieve photoresponsiveness in a light-inert ASTP system by physically introducing a phototrigger with the aid of a Trojan horse. The ASTP system formed from sodium laurate (SL) and dodecyltributylammonium bromide (DBAB) does not show light responsiveness by physically mixing a light-responsive azobenzene compound, 2-(4-(phenyldiazenyl)phenoxy)acetate sodium (Azo). However, in the presence of the host-guest complex SL@β-CD formed from β-CD and sodium laurate (SL), the ASTP turns quickly into a homogeneous suspension under visible light, which recovers to the original ASTP state again under 365 nm UV irradiation. Because the SL@β-CD complex exists harmonically with the ASTP system, it can be viewed as a "Trojan horse" that becomes fatal only when the encapsulated SL is triggered to release. In the presence of the Trojan horse, the photoresponsiveness of the ASTP system can be manipulated reversibly by alternatively exerting UV and visible light. Using this strategy, we are able to collect trace amounts of oily components from water. The current strategy points out that it is possible to achieve light responsiveness in light-inert systems with a physical method, which may have profound impact on both the fundamental and applied science.

We report an easy process for the fabrication of highly emissive tetraphenylethylene (TPE) with leaf-like architecture through a simple physical inter-locking of its rotating phenyl rings directed by polydimethylsiloxane (PDMS) film. The results reveal that the swelling and deswelling of PDMS film in TPE solution cause the emissive molecules to penetrate into the PDMS film and aggregate onto the film surface, respectively, which eventually emerge into a strongly fluorescent assembly. Mechanistically, when the PDMS deswells upon drying, the buckling effect of the material guides the adsorbed TPE molecules to assemble into closely packed architectures, as observed using a confocal microscopy . The results from the theoretical calculations suggest that the existence of through-space Ar-C···π electronic cloud interaction locks the rotation of phenyl rings in the assembled TPE architecture. This kind of electronic cloud delocalization starts off radiative decay process, endowing the material with a photophysical phenomenon of aggregation-induced emission (AIE). Interestingly, the developed assembly shows a sensory capability as confirmed by the progressive variation on the fluorescence of material as a function of mechanical strain applied. The current work offers an easy route to design supramolecular architectures possessing AIE attribute without introducing any chemical substituent.

The evolution and distribution of the aging precipitates in 1460 Al-Li alloy with high Li concentration (2.14%, mass fraction) during T6 aging and two-step T8 (4% predeformation) aging were investigated through TEM. The aging precipitates include δ′ (Al3Li) and T1 (Al2CuLi) phases, of which the δ′ phases are formed first in grain interiors. A lot of δ′/GPI/δ′ composite precipitates in which GPI zones are flanked with a pair of δ′ phases, are formed at 145 °C of T6 aging, which are thermally stable. At 160 °C and 175 °C of T6 aging, many T1 phases nucleate first at subgrain boundaries and grain boundaries, and then form and grow within grains. As to the T8 aging, the δ′/GPI/δ′ composite precipitates are formed during the first-step aging at 130 °C for 20 h, which are thermally stable during the second-step aging at 160 °C. The plastic predeformation accelerates T1 nucleation within grains during the second-step aging at 160 °C.

Two-dimensional (2D) boron nitride nanosheets (BNNSs) were chemically exfoliated from bulk boron nitride and coated onto the surface of a poly(ethylene oxide) (PEO)-based electrolyte through a dry-pressing transfer process. The fabricated BNNSs coating formed a robust interfacial layer to improve the chemical and mechanical stability of the PEO-based electrolyte, leading to the enhanced performance of solid-state Li metal batteries.

A major challenge toward realizing high-performance aqueous lithium batteries (ALBs) is the utilization of a metallic lithium anode. However, an ideal solid electrolyte that can protect metallic lithium from reacting with aqueous solutions while still maintaining a high lithium ion conduction is not currently available. One obstacle is the lack of a reliable experimental tool to differentiate the conduction behaviour of H+ and Li+ ions in a solid electrolyte. Here, by correlating neutron and electron spectroscopy, we quantitatively reveal the mobility and lattice occupancy of the two ions individually in protonated cubic Li6.25Al0.25La3Zr2O12 (LLZO). Our results not only highlight LLZO as a potential effective separation layer for ALBs but also present a robust method to quantify the mobility of individual mobile ions in solid-state ion conductors.