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Lifetime-coded optical multiplexing has attracted wide attention due to avoiding spectral overlap and background interference. At present, most of the materials used for lifetime-coded multiplexing...

Polyethylene oxide (PEO) was one of the most classic and widely used solid polymer electrolyte matrixes. In this work, we added the previously synthesized titanium dioxide (B-P25) fillers with oxygen vacancies to the PEO-LiClO4 solid electrolyte system. It is found that compared with the pristine P25 fillers, the oxygen vacancies lead to the decrease of ionic conductivity and the Li+ transference number. Infrared and Raman spectroscopy shows that the introduction of oxygen vacancies lead to the formation of Li+-ClO4− ion pairs and the decrease of carrier concentration resulted in the decrease of Li+ conductivity. Further theoretical calculations verified that this is due to the preferential combination of oxygen vacancies and ether oxygen atoms of PEO. This finding effectively supplements the effect of oxide oxygen vacancies on the conduction of Li+ in the PEO matrix, and not all oxygen vacancies are beneficial to the conduction of Li+ ions in the PEO matrix.

The development of detection method for aflatoxin gene cluster in Aspergillus flavus and Aspergillus parasiticusis is an effective approach to prevent the widespread of aflatoxins, which are considered as extremely, toxic substances. Herein, a hairpin DNA-assisted fluorescence probe switch based on Forster resonant energy transfer (FRET) was designed. In this work, the two terminals of hairpin DNA probe were combined with CdTe/CdS quantum dots as donor and gold nanoparticles (AuNPs) as acceptor respectively to fabricate the FRET hairpin probe switch, which were utilized to detect the aflatoxigenic fragment of aflD genes for the first time. In the absence of target DNA, the hairpin probe formed the double stem loops state to trigger the FRET to induce the fluorescence-quenching (turning off). With the addition of target DNA, the specific interaction between target and hairpin probe switch brought about the separation of fluorescent energy donor–acceptor pairs to create an increasing fluorescence response (turning on). Consequently, the fluorescence intensity recovers can be employed to detect aflD genes in homogenous phase through optical responses. This proposed FRET hairpin probe switch performed a great limit of detection of 0.02 nM with a linear range of 0.05–200 nM under optimal conditions. Furthermore, the feasibility of the fabricated strategy was demonstrated in fermented soybean paste with the advantages of simplicity, rapidity, and sensitivity, which indicated that this method exhibited the potential and practicability in foodborne biological samples.

A facile method was developed to prepare carbon dots(CDs) by pyrolysis and etching of coffee residue. The as-prepared CDs show uniform spherical nanoparticles with an average size of 2.3 nm and exhibit excitation-dependent fluorescence emissions. Moreover, CDs also exhibit strong fluorescence quenching to nitro compounds and metal ions in both water and ethanol solutions, which could act as a platform for dual detection of PA(picric acid) and Fe3+ ions with low detection limits of 0.26 and 0.83 µmol/L, respectively. This work provides a novel method for preparation of environmental-friendly fluorescent CDs and shows their potential applications in photoluminescence sensors.

Novel and highly efficient peroxidase mimics CDs@Cu-ZIF-8 are designed and prepared by a feasible solvent-free method. The introduction of copper ions enables non-active ZIF-8 nanocrystals to have good peroxidase-like activities, which can catalyse the reduction of hydrogen peroxide (H2O2). Furthermore, luminescent CDs are embedded into Cu-ZIF-8 nanocrystals to avoid aggregation, and particularly to construct a host–guest system with higher enzymatic catalytic activity. The synergy of CDs and the Cu-ZIF-8 matrix enhances the host–guest electron transfer, and meanwhile, accelerates the catalytic electron transfer process. Thus, CD@Cu-ZIF-8 displays superior peroxidase-like activity and glutathione (GSH) detection to pure CDs, Cu-ZIF-8 and CD@ZIF-8, and the limit of detection (LOD) reaches 0.15 μM. Considering the variety of CDs and MOFs with different metal centers and frameworks, the design strategy presented in this work will provide more opportunities to prepare CD@MOF nanozymes for being applied in the fields of biological analysis and actual biological environments.

Traditional SAPO-34 zeolites synthesized using trimethylamine (TEA) as organic templates have relatively large particle size and limited MTO performance. In this work, SAPO-34 plates have been successfully synthesized using TEA as templates with the presence of polyethylene glycol (PEG) as an assisted template. Two-step crystallization is utilized in the concentrated gel system to control the particle size in the range of 0.9–1.2 μm. The MTO catalysis shows that the as-synthesized SAPO-34 plates exhibit enhanced catalytic performance. At 99% conversion, it has a catalytic lifetime (326 min) that is eight times longer than that of the conventional sample and 80% selectivity for light olefins. Moreover, the NMR study reveals the distinct crystallization process of SAPO-34 in two gel systems. Different from silicon being the activated species and the crystal center in a normal gel system, the aluminophosphate framework is first generated and then silicon gradually enters to replace Al or P in the concentrated gel system.

Titanium silicalite-1 (TS-1) zeolite, as a promising shape-selective catalyst, has excellent catalytic activity in many oxidation reactions. However, there are still challenges to rapidly synthesize TS-1 and achieve a high content of Ti in TS-1 without anatase TiO2. In this work, a high-efficiency strategy has been proposed by using 1,3,5-benzenetricarboxylic acid (H3BTC) as a crystallization modifier to rapidly synthesize enhanced-Ti TS-1 zeolite without extra-framework anatase TiO2. In such a synthetic system, a mixed liquid–solid precursor phase is formed within 4.5 hours, and then TS-1 crystals can be produced within one day based on the special combination mechanism of liquid-phase and solid-phase conversion. Ti species enter into the TS-1 framework by the transformation from the liquid phase to crystals as well as by the in situ transformation of the solid phase, which makes the content of framework Ti increase significantly, and the Si/Ti ratio can reach 48.5 without any anatase TiO2. In the epoxidation of 1-hexene with H2O2 as an oxidant, the conversion of alkene over the synthesized TS-1 was improved by 8.01% compared to the traditional TS-1 (18.11% vs. 10.10%). The high-efficiency strategy reported in this paper will provide new opportunities for further promoting the industrial application of TS-1 zeolite.

In this study, we isolated an endophytic Streptomyces sp. strain, WP-1, from surface-sterilized barks of Pinus dabeshanensis, an endangered Chinese plant. WP-1 showed strong antifungal activity against diverse pathogenic fungi, such as Fusarium oxysporum, Rhizoctonia solani, Phytophthora infestan, and Candida albicans. Based on phylogenetic analyses, preliminary identification suggested that the WP-1 strain belonged to the genus Streptomyces. Column chromatogram and HPLC were employed to isolate the primary antifungal component from the culture medium of WP-1, and it was identified as the methylpentaene macrolide antibiotic, fungichromin (FC). In this study, for the first time, using in vitro bioassay studies, we revealed that FC strongly inhibited mycelial growth and conidia germination in Fusarium oxysporum. The median inhibitory concentration of FC was found to be 3.80 mg/L. The fermentation conditions of the WP-1 strain were further investigated to improve FC production. We found that supplementation of the synthetic medium with oils (soybean oil, oleic acid, and so on), particularly during the initial stage of fermentation, significantly increased the FC yield. Ammonium-trapping agent (magnesium phosphate) was used as an additive to increase FC yield to 5741.7 mg/L. It was 2.9-fold more as compared to the highest FC yield reported so far where Streptomyces padanus PMS-702 was used for FC production. • Isolation and identification of a fungichromin-producing endophytic actinomycete WP-1 strain. • Fungichromin production was significantly improved via oils and ammonium-trapping agents addition. • Discovery of the antifungal activity of fungichromin against Fusarium oxysporum.

Our conceived approach based on the directed assembly of functional metal-organic squares (MOSs), 4-membered ring (4MR) building units, permitted the construction of two novel zeolite-like supramolecular assemblies (ZSAs), namely [Co4 (ImDC)4 (En)4 ]⋅9 H2 O⋅1.5 DMF (ZSA-10) and [Co4 (ImDC)4 (En)4 ]⋅7 H2 O (ZSA-11) (H3 ImDC=4,5-imidazoledicarboxylic acid, En=ethylenediamine, DMF=N,N-dimethylformamide). The elected MOSs encompass both trans- and cis-coordinated nodes, offering complementary peripheral functional groups for their directed assembly into zeolite-like topologies via supramolecular hydrogen bonding interactions. Distinctly, ZSA-10 possesses the underling MER zeolite topology and is the only pure MER framework material (without any supporting templates) exhibiting permanent porosity up to now. ZSA-11 has the underlying ABW topology together with one type of narrow channel.

Carbon dots (CDs) are emerging as a new class of carbon nanomaterials, which have inspired growing interest for their widespread applications in anti-counterfeiting, sensing, bioimaging, optoelectronic and energy-related fields. In terms of the concept of host-guest assembly, immobilizing CDs into porous materials (PMs) has proven to be an effective strategy to avoid the aggregation of bare CDs in solid state, in particular, the host-guest synergy with both merits of CDs and PMs affords composites promising properties in afterglow and tunable emissions, as well as optimizes their performance in optics, catalysis, and energy storage. This Minireview summarizes the recent progress in the research of CDs@PMs, and highlights synthetic strategies of constructing composites and roles of porous matrices in boosting the applications of CDs in diverse areas. The prospect of future exploration and challenges are proposed for designing advanced CDs-based functional nanocomposite materials.

In the search for highly effective modulators addressing ABCG2-mediated MDR, 23 pyrimidines were synthesized and biologically assessed. Seven derivatives with (a) nitrogen- and/or halogen-containing residue(s) had extraordinary potencies against ABCG2 (IC

Organic afterglow materials are highly desirable for optoelectronic applications, but they usually suffer from complex preparation process, low quantum efficiency, and short lifetime due to the ult...

The position of Pd species in/on zeolites is crucial for activity of metal/metal oxide catalysts. It is still a challenge to highly disperse and stabilize the metal species on zeolites and shorten ...

The development of wide-spectrum responsive photocatalysts for efficient formaldehyde (HCHO) removal is highly desired yet remains a great challenge. Here we successfully converted zeolitic imidazolate framework-8 (ZIF-8), one of the most well-studied metal–organic frameworks (MOFs), from routine ultraviolet-driven to novel broad-spectrum-driven photocatalyst via a facile thermal treatment. The isocyanate groups (–N Created by potrace 1.16, written by Peter Selinger 2001-2019 CO) formed in the thermally treated ZIF-8 (ZIF-8-T) is crucial in enabling the superior photocatalytic performance in formaldehyde degradation. Specifically, the best-performing ZIF-8-T sample showed around 2.1 and 9.4 times the HCHO adsorption amount and the solar photocatalytic degradation rate, respectively, of pristine ZIF-8. In addition, ZIF-8-T exhibited visible light (λ ≥ 400 nm) photocatalytic HCHO degradation performance, photo-converting 72% and nearly 100% of 20 ppm and 10 ppm HCHO within 1 hour, respectively. This work affords new insights and knowledge that inspire and inform the design and development of MOF-based photocatalysts with broad-spectrum responses for efficient air purification operations., The isocyanate groups (–NCO) derived from –NC– bonds in the organic ligands enables the thermally treated ZIF-8 to act as wide-spectrum photocatalyst.

Background Stearoyl-CoA desaturase-1 (SCD1) is reported to play essential roles in cancer stemness among several cancers. Our previous research revealed significant overexpression of SCD1 in primary gastric cancer stem cells (GCSCs), with its functional role still unknown. Methods We stably established three primary GCSCs by sphere-forming assays and flow cytometry. Protein quantification and bioinformatics analysis were performed to reveal the differential protein pattern. Lentivirus-based small-interfering RNA (siRNA) knockdown and pharmacological inhibition approaches were used to characterise the function and molecular mechanism role of SCD1 in the regulation of GC stemness and tumour metastasis capacity both in vitro and in vivo. Results SCD1 was found to increase the population of GCSCs, whereas its suppression by an SCD1 inhibitor or knockdown by siRNA attenuated the stemness of GCSCs, including chemotherapy resistance and sphere-forming ability. Furthermore, SCD1 suppression reversed epithelial-to-mesenchymal transition and reduced the GC metastasis probability both in vitro and in vivo. Downregulation of SCD1 in GCSCs was associated with the expression of Yes-associated protein (YAP), a key protein in the Hippo pathway, and nuclear YAP translocation was also blocked by the SCD1 decrease. Conclusions SCD1 promotes GCSC stemness through the Hippo/YAP pathway. Targeting SCD1 might be a novel therapeutic strategy, especially to suppress GC metastasis and sensitise chemotherapy.

Multi-target detection has been widely applied for the sensitive measurement of cancer-related biomarkers; however, the design and application of single platforms for diverse target detection are still challenging. Herein, a robust and sensitive electrochemiluminescence (ECL) biosensing platform was constructed for the measurement of microRNA-21 (miRNA-21) and mucin 1 (MUC1) based on dual catalytic hairpin assembly (DCHA). The catalytic hairpin assembly (CHA) process (Cycle I) was initiated by the target miRNA-21 to introduce abundant CdS:Mn quantum dots (CdS:Mn QDs) on the electrode surface, leading to a considerable ECL response and the sensitive detection of miRNA-21 with a limit of detection as low as 11 aM. Subsequently, the second CHA process (Cycle II) was triggered by the MUC1-aptamer complex, which allowed copious amounts of Au nanoparticles (AuNPs) to approach the CdS:Mn QDs. A decreased ECL signal was obtained due to the ECL resonance energy transfer (ECL-RET) effect between the CdS:Mn QDs and AuNPs; meanwhile, MUC1 was sensitively detected with a limit of detection of 0.40 fg mL−1. This single sensing platform achieved dual cancer-related biomarker detection, which could provide a rational approach for future clinical analyse.

As one of the highly crystalline porous materials, metal–organic frameworks (MOFs) have drawn immense attention due to their diverse structures and a wide variety of applications. In this study, [In3(ipbp)2(μ2-OH)(μ2-O)3] (1) that has a three-dimensional framework, including two types of cages with cuboctahedra and trigonal antiprism configurations, has been successfully synthesized based on the zwitterionic ligand 1-(3,5-dicarboxyphenyl)-4,4′-bipyridinium bromide (H2(ipbp)Br). Strikingly, a relatively rare trapeziform metal layer consisting of In3+, μ2-OH, μ2-O, carboxyl, and nitrogen from the ligand appears in the structure of 1. Benefitting from the formation of the ipbp radicals under UV light irradiation, compound 1 exhibits photochromic property that can transform the color from yellow to green. Moreover, it possesses commendable Cr(VI) removal capacity with the maximum adsorption amount of 74.4 mg·g−1 due to the surface electrostatic interaction between the crystal surface and Cr(VI) in the aqueous system. This work will promote the design of functional MOFs that show potential applications in UV light detection and removal of oxyanions.

Confining carbon dots (CDs) in zeolites may boost the thermally activated delayed fluorescence (TADF) emission. However, so far only blue-emissive CD-based TADF materials are reported, and rationally tuning the TADF emission of these materials remains challenging. Herein, by in situ embedding different emissive CDs into a zeolite matrix, we have successfully prepared a series of CD@zeolite composites with tunable TADF emission from blue to green by utilizing energy transfer (ET) between confined CDs. The as-prepared CD@zeolite composites exhibit lifetimes varying from 271 ms to 860 ms and quantum yields ranging from 20% to 42%. The ET process occurs from the singlet excited state of the blue emissive CD donor to the singlet excited state of green emissive CD acceptors with different polymerization degrees, promoting tunable TADF with cyan, mint green and olive green emission. The design concept proposed in this work may open a way to judicious tuning of the emission of TADF materials, and thus may broaden the applications of CD-based TADF materials.

Growing interest in photochromic materials has largely stimulated researchers in this field to synthesize inorganic–organic materials that are composed of photochromic molecules such as viologen derivatives, naphthalene diimide (NDI) derivatives, and diarylethene derivatives. However, the requirement of an elaborate structural design, complicated synthesis, and high cost remain the issues that need to be addressed before the photochromic materials can be accepted by the market. Their synthesis using low-cost deep-eutectic solvents (DESs) may offer new opportunities to provide cost-effective reaction routes for large-scale synthesis of photochromic materials. We present a multifunctional photochromic inorganic–organic complex |C10H10N2|[GaF(C2O4)2], which is constructed from a nonphotochromic 4,4′-bipyridine ligand and oxalate derived from low-cost DES components. The complex exhibits intriguing photochromic behavior with a wide range of photo-response from UV to visible light and an ultralong-lived charge-separated state. Moreover, it possesses unprecedented tunable photocurrent responses and photocatalytic properties.

Two new sterol derivatives, namely ergosterimide B (1) and demethylincisterol A5 (2), along with eleven known metabolites (3���13), were isolated from the rice fermentation culture of Aspergillus tubingensis YP-2. The chemical structures were elucidated by detailed NMR and MS spectroscopic data and by comparison with reported data. Newly isolated compound 2 and known compound 3 were evaluated for their cytotoxicities against the A549 and HepG2 cell lines. Compound 2 showed weak activities with IC50 values of 11.05 and 19.15 ��M, respectively, while 3 exhibited cytotoxicities with IC50 values of 5.34 and 12.03 ��M, respectively, against the tested cell lines.

Phosphate concentration above 10 mM reduces the production of many secondary metabolites; however, the phenomenon is not mechanistically understood yet. Specifically, the problem of phosphorus limitation in antibiotic production remains unresolved. This study investigates the phosphorus inhibition effect on spinosad production and alleviates it by calcium and phosphate supplementation to fermentation media. Furthermore, we examined the mechanism of fatty acids induced increase in polyketides production. NaH2PO4 was found to be the most effective phosphate. Under the optimal phosphate condition, the maximal spinosad production reached 520 mg/L, showing a 1.65-fold increase over the control treatment. In the NaH2PO4-CaCO3 system, the de novo fatty acid biosynthesis was significantly downregulated while spinosad biosynthesis and β-oxidation were upregulated. The coordination of de novo fatty acid biosynthesis and β-oxidation promoted intracellular acetyl-CoA concentration. The results demonstrate that NaH2PO4-CaCO3 combined addition is a simple and effective strategy to alleviate phosphorus inhibition effect through the regulation of fatty acid metabolism and accumulation of immediate precursors. This information improves our understanding of phosphates' influence on the large-scale production of polyketides.

A supramolecular network [H4bdcbpy(NO3)2·H2O] (H4bdcbpy = 1,1′-Bis(3,5-dicarboxybenzyl)-4,4′-bipyridinium) (1) was prepared by a zwitterionic viologen carboxylate ligand in hydrothermal synthesis conditions. The as-synthesized (1) has been well characterized by means of single-crystal/powder X-ray diffraction, elemental analysis, thermogravimetric analysis and infrared and UV-vis spectroscopy. This compound possesses a three-dimensional supramolecular structure, formed by the hydrogen bond and π–π interaction between the organic ligands. This compound shows photochromic properties under UV light, as well as vapochromic behavior upon exposure to volatile amines and ammonia, in which the electron transfer from electron-rich parts to the electron-deficient viologen unit gives rise to colored radicals. Moreover, the intensive intermolecular H-bonding networks in 1 endows it with a proton conductivity of 1.06 × 10−3 S cm−1 in water at 90 °C.

Background : Canida albicans can cause opportunistic infections ranging from superficial mucous membrane lesions to life-threatening disease. The aim of this study is to investigate the antifungal effect of photodynamic therapy (PDT) mediated by curcumin (CUR) on C. albicans biofilms in vitro. Methods : One standard strain ATCC 90028 and two clinical isolates from HIV (CCA1) and oral lichen planus (CCA2) patients’ oral cavities were used in this study. Biofilms were photosensitized with 60 μM CUR and irradiated by light emitting diode (LED) under the wavelength of 455 nm and energy densities of 2.64, 5.28, 7.92, 10.56, 13.2 J/cm2. Then the antifungal effects of CUR-PDT were evaluated by XTT reduction assay and confocal light scanning microscopy (CLSM) observations. The effects of CUR-PDT on the expression levels of hypha-specific and biofilm-related genes including EFG1, UME6, HGC1 and ECE1 were assessed by quantitative Real-time PCR (qRT-PCR) method. Results : The inhibition rates after CUR-PDT in three biofilms(ATCC 90028, CCA1, CCA2)were 90.87%, 66.44% and 86.74% respectively (p Conclusions : Curcumin-mediated PDT could effectively inactivateCandida albicans biofilms in vitro. Expression of genes involved in biofilms formation were downregulated after CUR-PDT.

Room-temperature phosphorescence (RTP) and thermally activated delayed fluorescence (TADF) materials with long afterglow lifetimes have aroused considerable interest. Here, we successfully achieve the modulation of RTP and TADF properties in a carbon dots (CDs)-in-zeolite system based on different organic templates via an in situ solvothermal synthetic method. Benefitting from the efficient stabilizing effect of triplet states of CDs by SBT zeolite matrix, CDs@SBT-1 with a larger singlet–triplet energy gap (ΔEST) of 0.36 eV exhibits predominant RTP with a lifetime of 574 ms, while CDs@SBT-2 with a smaller ΔEST value of 0.18 eV shows TADF with a lifetime of 153 ms. Further investigations reveal that different organic templates result in different CDs structures, thus modulating the ΔEST values of CDs@zeolites. This work demonstrates a facile strategy to modulate the afterglow properties of CDs@zeolite composites, which opens the possibility of designing the novel afterglow materials desired for various adv...

Metal sulfides have been drawing more and more attention as electrode materials in batteries due to their high theoretical capacities. However, the volume expansion and loss of active materials are two major problems, hindering further improvement in their electrochemical performances. Herein, a strategy based on physical confinement/chemical adsorption is proposed to fabricate CoS and Co9S8 electrodes for advanced lithium batteries. Via a facile two-step method, porous C/CNT micro/nano-spheres embedding cobalt sulfide nanoparticles are successfully fabricated, in which sulfur is immobilized by C S bonds. Physically, the porous C/CNT micro/nano-spheres well accommodate the volume change and inhibit the loss of active materials. Chemically, the sulfur species are anchored by C S bonds to alleviate the migration and loss. Assembled as lithium battery anodes, the porous cobalt sulfide/carbon composites, particularly the CoS/C/CNT (CoS-0.4C) and Co9S8/C/CNT (Co9S8-0.8C), exhibit superior lithium storage properties to those without any complexing or any C S bonding. Furthermore, an in-situ electrochemical measurement is proposed to detect the existence of Li2S, which is helpful to understand the mechanism of conversion reaction-based metal sulfides.

The encapsulation of polyoxomolybdic cobalt (CoPMA) and polyoxomolybdic acid (PMA) within the Zr-based metal–organic frameworks (Zr-MOFs) of UiO-bpy (connected by 2,2′-bipyridine-5,5′-dicarboxylic ...

Carbon dots (CDs) with red-emitting room-temperature phosphorescence (RTP) are rarely reported because of the increasing nonradiative decay of the excited states and the decreasing energy gap between the excited states and ground states. Herein, we demonstrate a facile strategy for modulating the RTP properties of CDs in terms of donor–acceptor energy transfer (EnT) in the CDs-in-zeolite system. Upon tuning of the heteroatoms (Zn2+, Mn2+) doped in the aluminophosphate zeolite frameworks, CDs@zeolite composites with green and red phosphorescence have been prepared via in situ hydrothermal synthesis. In such composites, the zeolite matrix provides an efficient confinement role in stabilizing the triplet states of CDs. Significantly, the Mn-doped zeolite could act as an energy acceptor allowing EnT from excitons of CDs to the dopant in the host matrix, generating the intriguing red RTP behavior. This work provides an effective strategy for developing CD-based composite materials with special RTP emissions as well as new fields for applications., A strategy for modulating RTP property in terms of donor−acceptor energy transfer in a CDs-in-zeolite system is demonstrated. Red RTP is achieved for CDs@zeolite by doping Mn in zeolite matrix.

A novel three-dimensional open-framework titanophosphite Ti(HPO3)2 (denoted as JIS-15) has been ionothermally synthesized. JIS-15 possesses photovoltaic properties as an n-type semiconductor and exhibits remarkable photocatalytic activity for the degradation of rhodamine B (RhB) under visible light irradiation.

As a potential next-generation energy storage system, rechargeable magnesium batteries (RMBs) have been receiving increasing attention due to their excellent safety performance and high energy density. However, the sluggish kinetics of Mg2+ in the cathode has become one of the main bottlenecks restricting the development of RMBs. Here, we introduce oxygen vacancies to spherical NaV6O15 cross-linked with carbon nanotubes (CNTs) (denoted as SNVOX-CNT) as a cathode material to achieve an impressive long-term cycle life of RMBs. The introduction of oxygen vacancies can improve the electrochemical performance of the NaV6O15-X cathode material. Besides, owing to the introduction of CNTs, excellent internal/external electronic conduction paths can be built inside the whole electrode, which further achieves excellent electrochemical performance. Moreover, such a unique structure can efficiently improve the diffusion kinetics of Mg2+ (ranging from 1.28 × 10-12 to 7.21 × 10-12 cm2·s-1). Simulation calculations further prove that oxygen vacancies can cause Mg2+ to be inserted in NaV6O15-X. Our work proposes a strategy for the synergistic effect of oxygen vacancies and CNTs to improve the diffusion coefficient of Mg2+ in NaV6O15 and enhance the electrochemical performance of RMBs.

Supported palladium catalysts have attracted significant attention for use in cross-coupling reactions due to their recyclability. However, the inevitable progressive loss of Pd that occurs in the catalytic process deactivates the catalysts, which hinders their sustainable application. Herein, we report a zeolite-enhanced sustainable Pd catalyst for C–C cross-coupling reactions. Zeolite does a good job of acting as a sink for Pd2+ ions. This catalyst exhibits an excellent homogeneous catalytic performance by releasing Pd species from zeolite. In addition, the Pd2+ ions were successfully recaptured in a controlled catalytic system by combining the uniform microporous structure and good adsorption features of zeolite. The release/capture mechanism of the Pd species guaranteed the high loading and high dispersion of Pd on the recycled catalyst. The 0.84%Pd@USY catalysts were reused at least 10 times in water without an appreciable reduction in activity. This study presents a new perspective toward the design...

A new N-methoxy-1-pyridone alkaloid [chromenopyridin A (1)] and four known compounds (2–5) were isolated and identified from the endophytic fungus Penicillium nothofagi P-6, which was derived from the bark of the critically endangered conifer Abies beshanzuensis. Their structures were elucidated by extensive spectroscopic analyses and single-crystal X-ray diffraction. Among the isolates, compound 1 showed considerable cytotoxicities against the A549 and Hela human cancer cell lines, with IC50 values of 14.7 and 11.3 μM. In addition, compounds 1 and 4 exhibited potent antibacterial activity against Staphylococcus aureus with MIC values of 62.5 and 15.6 μg/mL, respectively.

Metal–organic frameworks (MOFs)-based fluorescent sensors have attracted much attention due to their high selectivity, sensitivity, and operability. However, the poor stability of MOFs seriously limits their applications in detecting toxic species in water system. Herein, taking advantage of the high chemical stability of the metal phosphonate bond, the easy crystallinity of carboxylate, and the π-conjugated benzene, a new luminescent MOF with three-dimensional network has been successfully synthesized using the predesigned 5-phosphonobenzene-1,3-dicarboxylic acid (H4pbdc) ligand. [Cd2(pbdc)(H2O)3] (1) not only possesses excellent stability in water and some organic solvents but also can remain structural integrity in acidic/alkaline aqueous solutions with pH value ranging from 4 to 10. Remarkably, 1 can efficiently and sensitively probe Cu2+, Al3+, and Fe3+ ions over other metal ions in an aqueous system. The quenching constant of Ksv and detection limit are 1.57 × 106 M–1 and 38.9 nM for Cu2+ ions, 2.86...

The solution combustion synthesis (SCS) has been widely used to prepare varieties of materials, especially oxides. Nevertheless, there are just a few reports applying the SCS to synthesize sulfides, and most of them are prepared under the protection of an inert atmosphere. As the counterpart of metal oxides, the metal sulfides (MSs) also play an important role in energy-related devices. Herein, a novel air atmospheric SCS is proposed to prepare classes of MSs and the corresponding carbon composites. Thanks to the evaporation and flash burning of ethanol, the O2 is consumed, protecting the MSs and the carbon nanotubes (CNTs) from oxidation; thus, the mesoporous CoS, NiS, Cu2S, and the CoS/CNT, NiS/CNT, Cu2S/CNT, can be easily and rapidly obtained by directly combusting in the air atmosphere. Compared to the conventional SCS for synthesizing the MSs, the equipment requirements of this proposed method are low, which is suitable for large-scale preparation. The lithium storage properties of MSs and MSs/CNTs a...

Absract The influence of oxygen-related thermal donors (TDs) on the performance of silicon heterojunction (SHJ) solar cells was explored experimentally in this paper. It is found that a certain number of thermal donors could do much harm to the performance of SHJ solar cells. The efficiency of SHJ solar cells is usually reduced by a value of ~ 1% absolute in the case of thermal donors with a concentration of nearly 1015 cm−3. The microwave photoconductance decay and Hall Effect studies have proved that the TDs can significantly reduce the carrier lifetime of n-type silicon substrate, but have no influence on the carrier mobility. Deep level transient spectroscopy (DLTS) measurements have further demonstrated that the TDs cause an energy level at Ec-0.13 eV with carrier capture cross-section of 10−15 cm2, which is responsible for the reduction of carrier lifetime and solar cell efficiency.

Extra-large-pore zeolites have attracted much interest because of their important applications for processing larger molecules. Although great progress has been made in academic science and industry, it is challenging to synthesize these materials. A new extra-large-pore zeolite SYSU-3 (Sun Yat-sen University no. 3) has been synthesized by using a novel sophoridine derivative as an organic structure-directing agent (OSDA). The framework structure was solved and refined using continuous rotation electron diffraction (cRED) data from nanosized crystals. SYSU-3 exhibits a new zeolite framework topology, which has the first 24×8×8-ring extra-large-pore system and a framework density (FD) as low as 11.4 T/1000 A3 . The unique skeleton of the OSDA plays an essential role in the formation of the distinctive zeolite structure. This work provides a new perspective for developing new zeolitic materials by using alkaloids as cost-effective OSDAs.

Oxygen precipitates (OPs) are unavoidably formed in Czochralski silicon (CZ-Si) containing relatively high concentrations of oxygen. The recombination behavior of such defects is also vital for bulk devices like solar cells as they can reduce the minority carrier lifetime and degrade the cell performance. In our experiments, the characteristics of oxygen precipitation in n-type CZ-Si are systematically investigated by means of Fourier transform infrared spectroscopy (FTIR), deep level transient spectroscopy (DLTS) and electron beam induced current (EBIC). It is found that the iron contamination in n-type CZ-Si can strongly influence the OPs generation and their electrical properties, whereas the hydrogen passivation can effectively reduce the recombination activity of OPs.

Uniform and hydrophilic carbon quantum dots (C-QDs) were synthesized by calcination and NaOH treatment from an organo-templated zeolite precursor. The color of luminescence was determined by the concentration of C-QDs. These variable-color C-QDs were applied for the first time in the imaging of Caenorhabditis elegans (C. elegans) as a model organism. The effects of C-QDs and possible behavioral changes in C. elegans were evaluated under treatment conditions. We could clearly observe distribution of C-QDs in C. elegans from the fluorescence images. Furthermore, we observed significant and detectable fluorescence quenching of the C-QDs by free radicals in C. elegans. Our work affirms that C-QDs can be developed as imaging probes and as potential fluorescent quantitative probes for detecting free radicals.

A cationic metal-organic framework (MOF), [Cu2 L(H2 O)2 ]⋅(NO3 )2 ⋅5.5 H2 O (1) has been successfully synthesized from a zwitterionic ligand 1,1'-bis(3,5-dicarboxyphenyl)-4,4'-bipyridinium chlorine ([H4 L]Cl2 ). The framework of compound 1 contains classical {Cu2 (O2 C)4 } paddlewheels, and possesses typical nbo-type topology and two types of channels with sizes of 5.0 and 15.54 A. Benefitting from the 3D cationic framework and high pore volume, compound 1 shows interesting selective adsorption ability for anionic dyes. Such material can be successfully employed in a chromatographic column to efficiently separate mixed dyes of Fluorescein Sodium and Methylene Blue. In addition, compound 1 exhibits excellent Cr2 O72- removal capacity with maximum adsorption amount of 222.5 mg g-1 , which ranks among the higher Cr2 O72- adsorption amounts of MOF materials ever reported, based on ion-exchange. The strategy to construct cationic MOFs based on zwitterionic ligands will promote the development of functional porous materials for the capture and removal of anionic pollutant species from contaminated liquid.

CuS nanospheres interconnected by the carbon nanotubes (CNTs) have been successfully prepared via a facile one-step microwave-assisted method. The component and microstructure of CuS/CNTs hybrid materials are well characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HR-TEM). Assembled as electrodes and tested in lithium ion batteries, the composites show impressive electrochemical performances. After 450 cycles, the CuS/0.1 CNT and CuS/0.5 CNT release more than 437 and 569 mAh g−1, respectively, at 400 mA g−1, which are superior to those of contrast experiments (pristine CuS and CuS mechanically mixing with CNTs). Even at the high current density of 6400 mA g−1, the CuS/0.5 CNT still displays the reversible capacity of about 400 mAh g−1. The improved performances can be ascribed to the inherently CNTs conducting network, boosting the interior electron transport and reaction kinetics, so that a significantly enhanced reversible capacities and rate capability can be realized. Furthermore, the surface properties and reaction kinetics of electrodes are also investigated via cyclic voltammetry (CV) and galvanostatic intermittence titration (GITT) measurements, proving the enhanced lithium storage properties.

A new germanate |H2(C4N3H13)|3[Ge7O14.5F2][Ge7O14F3]·2.5H2O (denoted as JLG-16) has been synthesized by using diethylenetriamine as the structure-directing agent under solvothermal conditions. Single-crystal structural analysis reveals that JLG-16 crystallizes in the monoclinic space group C2/c with a = 38.2008(15) A, b = 8.8262(4) A, c = 31.1789(13) A, and β = 108.5470(10)°. Its structure is made up of 4- and 5-coordinated Ge7 clusters. The alternating connection of 4- and 5-coordinated Ge7 clusters gives rise to a double-layered structure with 16- and 10-ring channels and a low framework density (11.2 Ge per 1000 A3). Carbon dots (CDs) formed in the mother liquid are in situ embedded into the JLG-16 crystals during the solvothermal crystallization process. The resulting CDs@JLG-16 composite thus exhibits excitation-dependent and temperature-responsive photoluminescence performances, which makes it possible to be used in optical temperature sensing.

This review article provides an overview of the contemporary research based on a tailor-made technique to understand the paramagnetic behavior of different polymer classes. The ubiquity of free radicals, including biradicals, triplet states, and point defects in polymer systems, has made EPR spectroscopy an indispensable tool in polymer science among other mainstream analytical techniques. The scope of EPR spectroscopy has broadened particularly due to the growing impulse to produce polymers with enhanced stability, to follow the charge transfer process in conducting polymers, to decipher the complex nanoscale dynamics of polymers, to fathom out the reaction mechanisms and kinetics of complex polymer reactions in a more facile way, and to carry out comprehensive structural and conformational analyses. Recent studies have hinted at the effectiveness of EPR spectroscopy in collecting data with sub-nanometer spatial resolution to decipher intrinsic intricacies, while keeping the pristine geometry unperturbed, a task yet not achievable with other conventional techniques. EPR spectroscopy is being applied in polymer science in multifarious ways, including, but not limited to, exploring the structure, conformation, and dynamics of polymer chain segments, degradation or defect studies, charge transfer properties, kinetics and reaction mechanisms especially of free radical polymerization reactions, and EPR imaging of the polymer matrix. A recent surge in its applications indicates that EPR spectroscopy is going to make a profound impact in the field of polymer science in upcoming years.

A novel strategy for selecting an additive based on understanding the influence of different functional groups on electrochemical characteristics is adopted. N,N-Diethylamino trimethylsilane (DEATMS) is tested as a bifunctional electrolyte additive to scavenge H2O and neutralize HF in the electrolyte and enhance the behaviour of graphite/LiNi0.5Co0.2Mn0.3O2 cells operating at a high voltage (4.5 V vs. Li/Li+) or elevated temperature (55 °C). With 2% DEATMS, no LiPF6 hydrolysis species is found after storage at 55 °C for 6 days, even with a moisture content of 2000 ppm in the electrolyte. In addition, the graphite/LiNi0.5Co0.2Mn0.3O2 cells containing DEATMS show cycling performances superior to those of the cells without DEATMS upon cycling for 100 cycles at a high voltage (85.5% vs. 72.0%) or high temperature (81.2% vs. 70.6%). The sacrificial oxidation of DEATMS on the cathode surface restricts direct contact between the electrolyte and cathode, improving the electrochemical performance. The ex situ surface analysis of the electrodes after cycling indicates that both the electrolyte decomposition and Mn dissolution are inhibited by the deposition of DEATMS oxidation products.

The excitation-dependent blue photoluminescent and oxygen-rich carbon nanodots (CNDs) have been prepared through calcinations and etching from MgAPO-44 zeolite occluding N-methylpiperidine organic template. The as-prepared CNDs, with about 3.4 nm in diameter, possess excellent dispersibility and photostability in both water and ethanol solution. These CNDs exhibit high selectivity and sensitivity for picric acid (PA) in detection of nitro and nitrophenol compounds in water and ethanol solution with the detection limit as low as 0.36 μM and Ksv of 1.30 × 105. Detection effect can be influenced by the concentration and pH value of CNDs in water solution. Study reveals that the efficient and fast detection of PA can be attributed to fluorescence resonance energy transfer (FRET).