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To meet the increasing energy demand, the research and development of efficient and clean fuel cells and metal-air batteries are of great significance. Under these circumstances, these hierarchically porous carbon nanomaterials obtained by pyrolysis of coordination polymers are regarded as excellent oxygen reduction catalysts and are expected to be used as air cathode materials. Herein, a type of 2-dimensional structure of InOF-26 has been thermally converted into ultrathin graphitized nitrogen-doped carbon nanosheets, denoted as NG-CNS. During the carbonization, the addition of ferric chloride assists in breaking the intermolecular forces between crystal structures, which is further conducive to the formation of carbon nanosheets with an improved graphitization degree. Meanwhile, the subsequent ammonia impregnation together with secondary calcination can readjust the coordination environment of nitrogen species in the carbonaceous matrix. The obtained product of NG-CNS exhibits excellent ORR performance with a high half-wave potential of 0.80 V, a large diffusion-limited current density of 6.00 mA cm−2, a small Tafel slope of 57.3 mV dec−1, to show unexpected practicability in Zn-air battery and Al-air battery. The relatively simple synthetic procedure, low cost, high repeatability, and satisfactory electrochemical performance of NG-CNS will provide a direction for the facile preparation of coordination polymer-derived carbon nanomaterials in energy storage and conversion applications.

As a biologically active macromolecule, deoxyribonucleic acid (DNA) has the advantages of sequence programmability and structure controllability and can accurately transmit sequence information to specific biological functions. Facing the complex internal microenvironment and heterogeneity in tumor treatment, the construction and applications of DNA-based nanomaterials have become a focus point of research. In particular, the hybridization of DNA molecules with other materials endows DNA-based nanomaterials with multiple functions such as targeting, stimulus responsiveness and regulations of biological activities, making DNA nanostructures great potential in the treatment of major human diseases. In this review, the construction and characteristics of DNA-based nanomaterials are introduced. Then, the functions and applications of DNA-based nanomaterials in the delivery of chemotherapy drugs and gene drugs, stimulus-responsive release and regulation of cell homeostasis are reviewed. Finally, the future development and challenges of DNA-based nanomaterials are prospected. We envision that DNA-based nanomaterials can enrich the nanomaterial system by rational design and synthesis and address the growing demands on biological and biomedical applications in the real world.

Achieving high-efficiency deep blue emitter with CIEy 10% has been a long-standing challenge for traditional fluorescent materials in organic light-emitting diodes (OLEDs). Here, we report the rational design and synthesis of two new deep blue luminogens: 4-(10-(4′-(9H-carbazol-9-yl)-2,5-dimethyl-[1,1′-biphenyl]-4-yl)anthracen-9-yl)benzonitrile (2M-ph-pCzAnBzt) and 4-(10-(4-(9H-carbazol-9-yl)-2,5-dimethylphenyl)anthracen-9-yl)benzonitrile (2M-pCzAnBzt). In particular, 2M-ph-pCzAnBzt produces saturated deep blue emissions in a non-doped electroluminescent device with an exceptionally high EQE of 10.44% and CIEx,y (0.151, 0.057). The unprecedented electroluminescent efficiency is attributed to the combined effects of higher-order reversed intersystem crossing and triplet-triplet up-conversion, which are supported by analysis of theoretical calculation, triplet sensitization experiments, as well as nanosecond transient absorption spectroscopy. This research offers a new approach to resolve the shortage of high efficiency deep blue fluorescent emitters.

Organic solid-state luminescent materials with high-efficiency deep-red emission have attracted considerable interest in recent years. Constructing donor-acceptor (D-A) type molecules has been one of most commonly used strategies to achieve deep-red emission, but it is always difficult to achieve high photoluminescence (PL) quantum yield (ηPL) due to forbidden charge-transfer state. Herein, we report a new D-A type molecule 4-(7-(4-(diphenylamino)phenyl)-9-oxo-9H-fluoren-2-yl)benzonitrile (TPA-FOCN), deriving from donor-acceptor-donor (D-A-D) type 2,7-bis(4-(diphenylamino)phenyl)-9H-fluoren-9-one (DTPA-FO) with a fluorescence maximum of 627 nm in solids. This molecular design enables a transformation of acceptor from fluorenone (FO) itself to 4-(9-oxo-9H-fluoren-2-yl)benzonitrile (FOCN). Compared with DTPA-FO, the introduction of cyanophenyl not only shifts the emission of TPA-FOCN to deep red with a fluorescence maximum of 668 nm in solids, but also maintains the high ηPL of 10%. Additionally, a solution-processed non-doped organic light-emitting diode (OLED) was fabricated with TPA-FOCN as emitter. TPA-FOCN device showed a maximum luminous efficiency of 0.13 cd/A and a maximum external quantum efficiency (EQE) of 0.22% with CIE coordinates of (0.64, 0.35). This work provides a valuable strategy for the rational design of high-efficiency deep-red emission materials using cyanophenyl as an ancillary acceptor.

There is a need to develop highly efficient materials for capturing uranium from nuclear wastewater. Here, 5-methylbenzotriazole modified graphene oxide (MBTA-GO) was used to adsorb U(VI) from aqueous solution. By the trials of different conditions, we found that the removal of U(VI) from acidic solution was strongly dependent on pH but independent of ionic strength. The U(VI) adsorption was perfectly conformed to the pseudo-second-order kinetics and the adsorption isotherms were simulated by the Langmuir model well. A high removal capacity (qmax = 264 mg/g) for U(VI) at pH 3.5 was obtained. XPS, EXAFS analyses and DFT calculations revealed that the mechanism of uranium capture was ascribed to (i) the surface complexation by benzotriazole and carboxyl groups (providing lone pair electrons) on MBTA-GO and (ii) enhanced synergistic coordination ability of delocalized π-bond of triazole group toward U due to the transfer of electrons from graphene sheet to benzotriazole. DFT calculations further demonstrated that benzotriazole displayed stronger binding with U(VI) compared to carboxyl group due to higher binding energy of [Side/Surface-U-MBTA-GO] (79.745, 54.986 kcal/mol) than [MBTA-GO–COOH–U] (27.131 kcal/mol). This work will provide valuable insight into designing novel nitrogen-containing adsorbents for practical application in wastewater treatment.

Tuft cells as a type of intestinal epithelial cells exist in epithelial barriers that play a critical role in immunity against parasite infection. It remains elusive about whether Tuft cells participate in bacterial eradication. Here we identify Sh2d6 as a signature marker for CD45+ Tuft-2 cells. Tuft-2 cells are derived from Lgr5+ intestinal stem cells but not bone marrow cells. Depletion of Tuft-2 cells is susceptible to bacterial infection. Tuft-2 cells quickly expand over bacterial infection and sense bacterial metabolite N-undecanoylglycine through vomeronasal receptor Vmn2r26. Mechanistically, Vmn2r26 engagement with N-undecanoylglycine activates GPCR-PLCγ2-Ca2+ signal axis, which initiates prostaglandin D2 (PGD2) production. PGD2 enhances mucus secretion of Goblet cells and induces antibacterial immunity. Moreover, Vmn2r26 signaling also promotes SpiB expression, which is responsible for Tuft-2 cell development and expansion over bacterial challenge. Our findings reveal a novel function of Tuft-2 cells in immunity against bacterial infection through Vmn2r26-mediated recognition of bacterial metabolites.

Creatine has been regarded as an essential dietary supplement due to its function of auxiliary energy supplement for muscles and neurons. Therefore, it is economical to effectively recover creatine from its wastewater by a separation technology with the characters of low energy consumption and environmental compatibility. In this work, a novel two-stage foam fractionation technology was developed for the desalination of the residual reactants and the effective recovery of creatine from its wastewater, successively. In the first stage, S-methylisothiourea sulfate was effectively removed into the foamate. Then, creatine was diluted and discharged into the storage tank with the creatine concentration of 1.5 g/L. In the second stage, a foam fractionation column with a vertical ellipsoid-shaped foam channel was used to concentrate creatine from the residual solution of the first stage. Under the optimal operating conditions, the enrichment ratio and the recovery percentage of creatine could reach as high as 25.3 and 83.3%, respectively. Through the two-stage foam fractionation, the total recovery percentage of creatine could achieve above 77.9%.

A series of novel phosphors such as Ba2Mg(PO4)2: Ag+ (BMPO: xAg), Ba2Mg(PO4)2: Sm3+ (BMPO: ySm) and Ba2Mg(PO4)2: Ag+, Sm3+ (BMPO: 1%Ag, ySm) were prepared by solid-state reaction method. Phase structure and luminescent properties of Ba2Mg(PO4)2 were explored. It is shown that, under the excitation of 278 nm DUV light, a broadband emission peak centered at 400 nm was obtained in BMPO: xAg at room temperature, which is attributed to the emission of the Ag+-Ag+ pairs. The optimum doping concentration of Ag+ in Ba2Mg(PO4)2 is 1 mol.%. And the main emission peaks of Ba2Mg(PO4)2: ySm are located at 564 nm, 600 nm and 645 nm, respectively, which are ascribed to the 4G5/2→6Hj (j = 5/2, 7/2, 9/2) transitions of Sm3+. In BMPO: 1%Ag, ySm, Ag+ can enhance the emission intensity of BMPO: ySm effectively via an energy transfer and/or absorptions with Sm3+.

An involution is a permutation whose compositional inverse is itself. Differentially 4-uniform involutions with high algebraic degree and high nonlinearity are important for the design of block ciphers because they possess good cryptographic properties and the same component can be used in both encryption circuit and decryption circuit. A well known differentially 4-uniform involution is the multiplicative inverse function, which is used as the S-boxes in AES and Camellia. Although many differential 4-uniform permutations have been constructed, there are only a few classes of differentially 4-uniform involutions. Recently, Charpin et al. presented an idea of constructing involutions, which is called piece by piece construction. With this method, we construct a family of differentially 4-uniform involutions with optimal algebraic degree and high nonlinearity. It is also shown with the help of computer that such involutions which are CCZ-inequivalent to the known differentially 4-uniform permutations in small number of even dimensions are constructed. Furthermore, the number of CCZ-inequivalent classes of our involutions over F 2 n increases exponentially when n increases.

As one of the most concerned radionuclides, 99technetium (Tc) usually exists as pertechnetate (TcO4−) and low-valence Tc(IV) in the environment. The speciation analysis of 99Tc plays a crucial role in understanding its toxicity, bioavailability and mobility, and developing effective remediation strategies. However, conventional hyphenated techniques for 99Tc speciation analysis usually require a large sample volume and tedious operation process. In this work, a simple but highly effective system, coupling capillary electrophoresis to inductively coupled plasma mass spectrometry (CE-ICP-MS), was developed to analyze total rhenium (TRe), Re(IV), and Re(VII), known as the analogues of technetium. It is worth noting that by the use of a sprayer with a direct-injection nebulizer as the interface, the CE and ICP-MS were efficiently coupled as an entity that shares the advantages of both modules. In comparison to conventional techniques, the proposed CE-ICP-MS dominates in terms of less sample consumption and higher sample introduction efficiency, thus results in improved sensitivity, reduced radioactive waste, and more significantly, alleviated radiological exposure to operators. Under the optimized conditions, LODs of 0.02 μg L−1 and 0.01 μg L−1 were obtained for TRe and Re(VII), respectively, with relative standard deviations (RSDs) better than 3.0%. In addition, the accuracy and practicability of this hyphenated system were validated by analyzing simulated Hanford site groundwater samples with satisfactory recovery and separation of TRe, Re(IV), and Re(VII). The proposed method retains the great potential for the speciation analysis of 99Tc in various samples.

The design of universal hosts suitable for different color dopants is still desired for efficient organic light-emitting diodes (OLEDs). In this work, two novel carbazole-formate based isomers (2CzMC and 4CzMC) with planar donor‒π‒acceptor (D‒π‒A) structures were designed and synthesized as the hosts for phosphorescent OLEDs (PhOLEDs). Due to the weak intramolecular charge transfer character and limited conjugation extensions, both 2CzMC and 4CzMC showed wide-bandgap emissions around 380 nm and high triplet energy levels (2.83 eV for 2CzMC, and 2.90 eV for 4CzMC). The photoluminescent spectra of 2CzMC and 4CzMC doped films with blue, green and red phosphors exhibited completely energy transfer from the hosts to the dopants. PhOLEDs devices with similar structures employing these doped film as emitter layers achieved excellent performance. Especially for 4CzMC-FIrpic based blue device, the external quantum efficiency (EQE) reached as high as 18.9%. This study showed a molecular design strategy to develop novel carbazole-based hosts for different color PhOLEDs.

Finding suitable routing paths for video streaming remains a challenging issue for multi-hop wireless networks, and previous studies rely on heuristics such as minimal hops or load-balancing. In this paper, we present an analytical approach that takes cross-layer factors into account and propose a new routing metric based on optimizing a queueing model that considers local loads, interferences and packet droppings. Through periodic traffic monitoring, routing nodes can estimate their capacity analytically, while a messaging protocol then helps establish the most efficient route. Simulation results obtained from using realistic video traffic have shown that our proposed routing metric outperforms existing routing metrics in several aspects. An analytical model that considers cross-layer factors for multi-hop wireless networks.Based on the analytical model, a novel routing metric is proposed for video streaming.Simulations using realistic video traffic verified our proposed metric.

99Tc is a β-emitting radionuclide with high fission yield, long half-time and it is urgent to remove Tc from liquid radioactive waste due to its potential toxicity for human. Herein, we presented a viologen-based cationic organic polymer (VBCOP) as a novel adsorbent with cationic sites and functional groups for efficient capture of Re/Tc(VII, IV) from aqueous medium. The results showed that this material could rapidly remove TcO4−/ReO4− from aqueous solution within 5 min and the maximum sorption capacity for Re(VII) could reach up to 444 mg g−1, and the distribution coefficient (Kd) towards Re(VII) and Tc(VII) reached 4.0 × 105 and 7.2 × 105 mL g−1, respectively. And more, the adsorption mechanism was also studied by X-ray photoelectron spectroscopy (XPS), Energy dispersive spectrometer (EDS) mapping and Ion chromatography (IC), the results suggested an ion-exchange process in which the Cl− in this material was replaced by ReO4−. Additionally, we investigated its adsorption mechanism towards low-valent Re which was prepared by reducing ReO4− with NaBH4, and the flexible tetraaza macrocycle introduced in the material chelated with Re(IV) was confirmed by X-ray photoelectron spectroscopy (XPS) and Extended X-ray absorption fine structure (EXAFS) analysis. In general, the research exhibits a new sorbent material that can remove both TcO4−/ReO4− and the low-valent Tc/Re, and provide a new strategy to treat radioactive waste containing Tc with different valences.

Nanoscale cobalt oxide (Co 3 O 4 ) particles are produced on three-dimensional nickel/silicon microchannel plates (Ni/Si-MCPs) as the active electrode materials in miniature supercapacitors. The Co 3 O 4 nano-flakes are fabricated on the surface and interior of the Ni/Si-MCPs by annealing the nano-structured Co(OH) 2 /Ni/Si-MCPs, and the electrical conductivity and capacitance retention are improved. The Ni/Si-MCPs covered with nano-flaked Co 3 O 4 supercapacitor offer smaller charging current leakage and higher discharging voltage than Ni/Si-MCPs electrodeposited with cobalt hydroxide {Co(OH) 2 }. Specific capacitance as high as 2.424 F/cm 2 or 606.24 F/g is achieved from the materials and the retention ratio is 89.85% after 2000 cycles thus demonstrating excellent potential in miniature supercapacitors.

Single white-emitting polymers are greatly desired to develop solution-processed white organic light-emitting diodes (WOLEDs) with simple fabrication processes and low-energy-consumption. Thermally activated delayed fluorescence (TADF) polymers harvesting both triplet and singlet excitons without heavy metals are promising candidates for solution-processable white-emitting devices. However, all-TADF polymers with efficient white emissions have not been well-developed. Herein, a new strategy is proposed to develop a series of all-TADF single white-emitting polymers for highly efficient non-doped solution-processed WOLEDs. A WOLED based on one of these polymers as the emitting layer achieves an EQEmax of 14.2%, a CEmax of 38.8 cd A−1, and a PEmax of 20.3 lm W−1 with the CIE coordinates of (0.33, 0.42) and (0.31, 0.39) at 100 cd m−2 and 2000 cd m−2, respectively. The double-channel trap-assisted and Langevin recombinations account for broad recombination zones, reduced formation of high-energy excitons on hosts and enhanced efficiency of PDTPT-1, 2&3 based OLEDs. As far as it is known, PDTPT-1 is the highest efficient white-emitting TADF polymer so far.

Icariin (ICA) and phosphorylated icariin (pICA) have excellent antiviral and antioxidant effects. However, whether ICA and pICA cause anti-LPS-induced intestinal damage remains unclear. In this study, we used Caco-2 cells as a model to investigate the protective effects of ICA and pICA on human colonic epithelial cells and explore their potential mechanisms. Our results indicated that ICA and pICA increased cell viability and decreased lactate dehydrogenase activity in Caco-2 cells. ICA and pICA also attenuated LPS-induced changes in intestinal epithelial cell permeability and reduced the levels of oxidative stress indicators, such as reactive oxygen species, malondialdehyde, and hydrogen peroxide, in Caco-2 cells. Antioxidant indicators, such as superoxide dismutase, glutathione peroxidase, catalase and total antioxidant capacity, were increased, while the levels of IL-1β, IL-6, IL-8 and TNF-α were reduced in the ICA and pICA groups. Furthermore, ICA and pICA decreased the gene abundance and enzyme activities of caspase-3, -8, -9 and -10 in Caco-2 cells. Our data suggest that ICA and pICA effectively attenuated LPS-induced changes in the oxidative stress, inflammation, apoptosis and intestinal permeability of intestinal epithelial cells. These findings provide new insight for treating LPS-induced intestinal injury.

Manganese-dioxide is electrodeposited on three-dimensional nickel/silicon microchannel plates (Si-MCPs) to produce miniature supercapacitors. The nanostructured MnO 2 thin film can be clearly observed from the channels and largely contribute to the capacitance. The compositions and morphology are characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The electrochemical properties are investigated by cyclic voltammetry (CV), galvanostatic charging–discharging, and electrochemical impedance spectroscopy (EIS) in a neutral 1 M Na 2 SO 4 solution which preserves the structure of the substrate. The capacitance is 0.961 F/cm 2 or 323.1 F/g and the retention ratio is 91.1% after 1000 cycles thereby demonstrating the robustness and durability.