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Formaldehyde-based resins are widely used in the field of wood adhesives. However, high formaldehyde emission is still a serious problem. Therefore, a low-toxic wood adhesive was successfully synth...

The conversion of ethyl levulinate (EL) to produce γ-valerolactone (GVL) through catalytic transfer hydrogenation (CTH) reaction plays a crucial role in the field of biomass catalytic conversion. In this work, a novel Zr-base catalyst with phenate group, phenolic hydroxyl and carboxyl in its structure was prepared by the co-precipitation of natural sources gallic acid and ZrCl4. It was found that Zr-GA has an excellent catalytic performance for this reaction and satisfactory GVL yield could be achieved. Besides, Zr-GA could be easily separated from the reaction system and reused at least six times without a significantly decrease in activity. Meanwhile, various characterizations had proved that Zr-GA is a porous material with acid–base bifunctional sites. The main reason for the high catalytic activity of the Zr-GA was that the synergetic effects of Lewis acid/base sites and Bronsted acid sites and appropriate textural properties. In addition, a possible reaction mechanism was proposed in conjunction with the poisoning experiment and previous reports. The heterogeneous catalyst Zr-GA prepared with gallic acid as a raw material has low cost and recyclability, and has great potential in green chemistry.

We present a novel generating function (GF) method for the self-condensing vinyl polymerization (SCVP) system with any initial distribution of preexisted polymers. Such a method was proven to be especially useful to investigate the semi-batch SCVP system allowing a sequence of feeding operations during the polymerization. Consequently, the number-, weight-, and z-average molecular weights as well as polydispersity index of hyperbranched polymers can be explicitly given, which are determined by predetermined feeding details and conversions in each polymerization step. These analytical results are further confirmed by the corresponding Monte Carlo simulation. Therefore the present GF method has provided a unified treatment on the semi-batch SCVP system. Accordingly, hyperbranched polymers with desired properties can be prepared by designing feeding details and presetting conversions at each step based on the present GF method.

Well-dispersed Ni-based nanocrystals with Ni/NiO hybrid nanostructure are built on cellulose-derived carbon (Ni-C-500), which exhibits outstanding photocatalytic performance in the hydrogen evolution from water. Control experiments confirm that the optimal nickel content in Ni-C-500 is 16 wt% and the optimum calcination temperature is 500 °C. The hydrogen evolution rate on Ni-C-500 in the presence of Eosin Y and triethanolamine (TEOA) reaches 13.5 mmol/gcat/h in the first hour, which is even higher than that on commercial Pt/C catalyst (11.4 mmol/gcat/h). The carbon support facilitates the transfer of photogenerated electrons from photosensitizer to Ni-based nanocrystals, efficiently preventing the recombination of photogenerated electrons and holes during the photocatalytic procedure. Density functional theory (DFT) calculations further demonstrate that the NiO islands on Ni(111) surface facilitate the adsorption of water molecules because of the interaction between the oxygen atom of NiO island and the hydrogen atom of water. Furthermore, produced Had around NiO island of Ni(111) surface is more easily to form hydrogen on Ni/NiO hybrid nanostructure than on clean Ni(111) surface. Ni/NiO hybrid nanostructure supported on biomass carbon for visible-light photocatalytic hydrogen evolution

The alcoholysis of furfuryl alcohol (FA) produce ethyl levulinate (EL) plays a crucial role in the field of biomass conversion. In this work, a novel Zr-base catalyst with sulfonic groups in its structure was prepared by the co-precipitation of sodium dodecyl benzene sulfonate and ZrOCl2 (Zr-DBS) under non-toxic conditions. It was found that Zr-DBS has an excellent catalytic performance for this reaction and an EL yield of 95.27% could be achieved. Besides, Zr-DBS could be easily separated from the reaction system and reused at least four times without a significantly decrease in activity. Meanwhile, Zr-DBS was characterized by Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption–desorption, inductively coupled plasma optical emission spectroscopy (ICP-OES) and Temperature-programmed desorption of ammonia (NH3-TPD). The main reason for the high catalytic activity of the Zr-DBS was that the synergetic effects of Lewis and Bronsted acid sites and appropriate textural properties.

Silicon (Si) is a promising anode for Lithum-ion batteries (LIBs) due to its high theoretical capacity (4200 mA h g−1). However, low initial Coulombic efficiency (ICE) and utilization efficiency due to volume expansion and poor conductivity hinder the practical application of Si. Herein, a facile coaxial electrospinning method is adopted to fabricate core–shell MXene/Si@C nanofibers, which have a number of unique structure advantages in improving the performance of Si particles. MXene nanosheets as a conductive substrate effectively bridge the Si particles and carbon shell to form the conductive network of the MXene/Si@C nanofibers, which is beneficial for fast charge transfer and facile lithium ion migration. The robust carbon shell and MXene nanosheets offer double accommodation for huge Si volume expansion during charge/discharge, maintaining the structural stability of the electrodes. Moreover, abundant functional group defects associated with the carbon shell and MXene synergistically contribute the additional capacitive capacity. Therefore, the obtained MXene/Si@C nanofibers as a freestanding anode for LIBs present remarkable electrochemical performance, i.e., a high capacity of 1083 mA h g−1 at 0.1 A g−1, an excellent rate performance of 301.1 mA h g−1 at 2 A g−1, high Si utilization efficiency up to 86% and a high ICE of over 78.4%. A facile coaxial electrospinning technique to construct the core–shell structure of multiple components has the potential to improve the electrochemical performance and facilitate the practical application of Si.

Environment-friendly approaches to directly convert atmospheric or flue gas CO2 to high-value chemicals is of great significance yet challenging. Protic ionic liquid catalysts with excellent properties are showing potential for the chemical fixation of CO2. In this work, a series of protic ionic liquids with different cationic structures have been synthesized, which bear hydrogen-bond interactions between unique N+–H bonds and the O atoms of epoxides and they are highly active catalytic sites. It was found that [AlTMG]Br shows obviously high/good catalytic activity for converting epoxides into cyclic carbonates with CO2 in the atmosphere or at even lower pressures (15% CO2 and 85% N2), outperforming the corresponding homogeneous catalyst analogues and superior to the known solvent- and metal-free catalytic systems. The results showed that under mild homogeneous catalytic reaction conditions, low-pressure CO2 can directly react with epoxides to give cyclic carbonates with excellent yields, without any co-catalysts such as metals, solvents and additives. In addition, the best catalyst [AlTMG]Br was proved to be robust with remarkable reusability, and displaying great potential for pollution reduction and industrial applications for the chemical conversion of atmospheric CO2.

Heavy metal ions are one of the main sources of water pollution. Most heavy metal ions are carcinogens that pose a threat to both ecological balance and human health. With the increasing demand for heavy metal detection, electrochemical detection is favorable due to its high sensitivity and efficiency. Here, after discussing the pollution sources and toxicities of Hg(ii), Cd(ii), As(iii), Pb(ii), UO2(ii), Tl(i), Cr(vi), Ag(i), and Cu(ii), we review a variety of recent electrochemical methods for detecting heavy metal ions. Compared with traditional methods, electrochemical methods are portable, fast, and cost-effective, and they can be adapted to various on-site inspection sites. Our review shows that the electrochemical detection of heavy metal ions is a very promising strategy that has attracted widespread attention and can be applied in agriculture, life science, clinical diagnosis, and analysis.

A novel bifunctional mesoporous zirconium–alizarin (Zr–AZN) hybrid was successfully synthesized by using a template-free self-assembly method. Systematic characterizations demonstrated that the catalyst possessed abundant acid–base couple sites (density: 0.47 vs. 0.79 mmol g−1, acid/base molar ratio: 0.59) and high porosity. Zr–AZN exhibits superior catalytic activity toward the Meerwein–Ponndorf–Verley (MPV) reduction of different biomass-derived carbonyl compounds compared to other catalysts, especially of ethyl levulinate (EL) to γ-valerolactone (GVL), in quantitative yields (96%) with a high GVL formation rate of 1205 μmol g−1 h−1 and TOF of 0.47 h−1. Theoretical calculations show that the structure of Zr–AZN with the highest catalytic activity originates from the complexation that occurs at the 1,2-dihydroxyl (catechol) group, instead of the 1-hydroxy-9-keto group. Furthermore, it also presents a higher activity and selectivity and a lower computed apparent activation free energy (19.4 vs. 29.3 kcal mol−1) for the hydrogenation of EL compared to Sn–AZN.

Zinc sulfide (ZnS), with a high theoretical capacity and low redox potential, is considered to be a promising anode material for use in sodium-ion batteries (SIBs). However, the dissolution of polysulfides and the structural collapse of ZnS will undoubtedly lead to inferior electrochemical properties. Herein, a bell string-like hollow ZnS-C nanofibers (ZnS@CNFs) film, which displays the unique structural integration of metal–organic framework (MOF)-derived hollow ZnS and three-dimensional (3D) N, S co-doped carbon nanofiber networks, is successfully fabricated via MOF-mediated electrospinning followed by solvothermal sulfuration and pyrolysis processes. The as-prepared ZnS@CNFs films, as free-standing anodes for SIBs, exhibit an excellent adsorption capacity for polysulfides and outstanding sodium storage performance owing to the existence of C–S bonds and conductive pathways. As a result, the ZnS@CNFs anodes show superior rate capabilities (258.3 mA h g−1 at 10 A g−1 with a high initial coulombic efficiency (ICE) of 88.4%) and cycling stability (decay ratio of 0.029% per cycle after 500 cycles at 1 A g−1). Finally, ZnS@CNFs//Na3V2(PO4)3 full-cells achieve a high energy density of 156.9 W h kg−1. This work sheds light on the potential application of MOF-derived ZnS anodes for use in high-performance SIBs.

Though being a promising anode material for sodium-ion batteries (SIBs), MoS2 with high theoretical capacity shows poor rate capability and rapid capacity decay, especially involving the conversion...

Herein, a novel single-enzyme-assisted dual recycle amplification strategy based on T7 exonuclease (T7 Exo) and a strand-displacement reaction (SDR) was designed to fabricate a photoelectrochemical (PEC) biosensor for sensitive microRNA-141 (miRNA-141) detection with the use of laminar bismuth tungstate (Bi2WO6) as photoactive material. Compared with a traditional enzyme-assisted dual recycle amplification strategy, the presented method could effectively refrain the enzyme interference reaction, reduce environmental sensitivity, and save cost. Here, hairpin DNA1 (H1) decorated on magnetic beads (MB) hybridized with target miRNA-141 to form an H1/miRNA-141 heteroduplex. With the introduction of hairpin DNA2 (H2)-labeled SiO2 (H2-SiO2), SDR was triggered between H2-SiO2 and H1, thus miRNA-141 was displaced from the H1/miRNA-141 heteroduplex and an H1/H2-SiO2 duplex was formed, realizing the reuse of the target. In the presence of T7 Exo, the H1/H2-SiO2 duplex was digested with the release of output DNA-SiO2. To enhance the target conversion rate, H1-MB was intactly released and cycled, which could initiate more T7 Exo digestion and free abundant output DNA-SiO2. Through such a process, a tiny miRNA-141 could induce substantial output DNA-SiO2, effectively improving the target amplification efficiency and detection sensitivity of a PEC biosensor. Furthermore, Bi2WO6 was modified on an electrode to provide a superior initial PEC signal due to its excellent electronic transformation capacity. With the introduction of output DNA-SiO2, the hairpin structure of H3 on the electrode was opened, making SiO2 close to the electrode surface, which significantly decreases the PEC signal. This work first established the PEC biosensor featuring a single-enzyme-assisted dual recycle amplification process for sensitive detection of biomarkers.

Low-cost sodium ion batteries (SIBs) have shown hopeful perspective for large-scale energy storage systems. However, the development of carbon anode materials with high gravimetric and volumetric capacity is still a challenge. Herein, we propose a novel dense and N, P co-doped carbon derived from high density crosslinked bacterial cellulose (BC) with hexachlorocyclotriphosphazene (HCCP), which simultaneously combines high gravimetric and volumetric capacity. The as-prepared electrode demonstrates a high reversible capacity of 223 mAh g−1 at 0.05 A g−1 and superior rate performance (145 mAh g−1 at 10 A g−1) based on the overall electrode materials. The full SIBs with this electrode show a high energy density (156.1 Wh kg−1) as well as a high Coulombic efficiency in the potential range of 0–4.2 V. Density functional theory (DFT) calculation and kinetic analysis reveals that the synergistic effect of N, P co-doped configurations contributes to the superior sodium storage performance. Moreover, this electrode possesses high pressing density of 1.40 g cm−3, which increases the volumetric capacity greatly (from 97.2 to 312.2 mAh cm−3). This work proposes a new idea towards the development of low-cost bacterial cellulose that can be used in practical applications for high gravimetric and volumetric performance SIBs.

The surface oxide layer of grain-oriented electrical steels was investigated by scanning electron microscopy. The formation mechanism and the influence on the glass film of the surface oxide layer were analyzed by the calculation of thermodynamics and kinetics. The surface oxide layer with 2.3 μm in thickness is mainly composed of SiO2, a small amount of FeO and Fe2SiO4. During the formation of surface oxide layer, the restriction factor was the diffusion of O in the oxide layer. At the initial stage of the decarburization annealing, FeO would be formed on the surface layer. SiO2 and silicate particles rapidly nucleated, grew and formed a granular oxide layer in the subsurface. As the oxidation layer thickens, the nucleation of new particles decreases, and the growth of oxide particles would be dominant. A lamellar oxide layer was formed between the surface oxide layer and the steel matrix, and eventually formed a typical three-layer structure. During the high temperature annealing, MgO mainly reacted with SiO2 and Fe2SiO4 in the surface oxide layer to form Mg2SiO4 and Fe2SiO4 would respond first, thus forming the glass film with average thickness of 4.87 μm.

A kind of natural, sustainable, and abundant biomass, chitin, is used as support to load palladium nanoparticles catalyst (Pd–chitin) for the transfer hydrogenation of phenolic compounds to ketones...

Single-atom catalysts (SACs) have attracted much attention due to their outstanding catalytic performance in heterogeneous catalysis. Here, we report a template sacrificial method to fabricate an a...

The transition of poly(vinylidene fluoride) (PVDF) α crystals to γ′ phase is, in general, unpredictable. In the present work, the related α–γ′ phase transition has been regulated through adjusting ...

Nanoparticle (NP)-based cancer immunotherapy has been extensively explored. However, the efficacy of existing strategies is often limited by the lack of effective tumor-specific antigens or the inability to present costimulatory signal or both. Here, we report a novel approach to overcoming these limitations through surface coating with dendritic-tumor fusion cell membranes, which present whole repertories of tumor-associated antigens in the presence of costimulatory molecules. Because antigen-presenting and costimulatory molecules are displayed on their surface, these NPs can efficiently penetrate immune organs and activate T cells. We show that these NPs can be utilized to prevent tumor development and regress established tumors, including tumors in the brain. We demonstrate that encapsulation of immune adjuvants further improves their efficacy. Due to their significant efficacy, the whole tumor antigen-presenting costimulatory NPs have the potential to be translated into clinical applications for treatment of various cancers.

Herein, we developed curcumin (Cur)-loaded porous poly­(lactic-co-glycolic acid) (pPLGA) nanoparticles (NPs) by the nanoprecipitation method. Dopamine (DA) was then self-polymerized to form a polydopamine (PDA) layer on the surface of the NPs, yielding Cur@pPLGA/PDA NPs that are able to act as both chemotherapeutic and photothermal agents. These NPs were further camouflaged with the red blood cell membrane (RBCM) to construct RBCM-Cur@pPLGA/PDA NPs. The RBCM-pPLGA/PDA NPs were around 200 nm in size and demonstrated photothermal performance in the near-infrared (NIR) region, with a potent conversion efficiency (35.2%). The blank carrier has favorable cytocompatibility, but when drug loaded the NPs can efficiently induce the death of cancer cells (particularly when combined with NIR laser treatment). Cellular uptake results revealed greater in vitro uptake of RBCM-Cur@pPLGA/PDA NPs than bare Cur@pPLGA/PDA NPs in the case of cancer cells but reduced macrophage phagocytosis. In vivo studies in mice showed that the RBCM-Cur@pPLGA/PDA NPs exhibited prolonged blood circulation times and excellent photothermal properties, allowing tumor-specific chemo-photothermal therapy. The RBCM-Cur@pPLGA/PDA NP platform presents great potential for targeted synergistic cancer treatments.

Poly(vinylidene fluoride) (PVDF) was blended with cetyltrimethylammonium bromide (CTAB)-modified illite through a solvent-casting method. The effects of the content of modified illite and temperature on γ-phase PVDF crystallization were studied in detail. Unmodified illite does not affect the crystallization of PVDF. By contrast, modified illite can effectively boost the nucleation of the γ-phase due to the electrostatic interaction between PVDF and modified illite. For PVDF with low contents of modified illite, for example, 0.5 wt %, the ability to obtain the γ-phase is enhanced at 155 °C compared with neat PVDF. Increasing the crystallization temperature or the content of modified illite facilitates to form more γ-phase. Blending of 2.0% modified illite generates a pure γ-phase regardless of crystallization temperature. The technique to prepare pure γ-phase PVDF materials has a huge potential application in the fabrication of cheap pyro- or piezoelectric devices.

Self-healing hydrogels based on degradable resources have developed rapidly in the past decade due to their extensive bioapplications with biosecurity. In this research, a new kind of cellulose-based self-healing hydrogel with bio-degradability is constructed through boronic ester linkage. The carboxyethyl cellulose-graft-phenylboronic acid (CMC–B(OH)2) was synthesized through condensation reaction conveniently and then hydrogels were prepared with dynamic boronic ester cross-linking. The chemical structures, microscopic morphologies, mechanical and self-healing properties of the hydrogels were investigated intensively through Fourier transform infrared (FT-IR) spectroscopy, rheological, SEM and tensile testing. The hydrogels formed instantly without any additional catalyst and exhibit excellent self-healing ability with good mechanical properties. Moreover, the hydrogels were applied for controlled release of doxorubicin (DOX·HCl) and showed a successive slow release profile. Importantly, the hydrogel exhibited excellent biocompatibility and show potential applications in controlled drug delivery, 3D cell culture and tissue engineering.

A series of novel betulin-28-hydrazone derivatives (7a-7o) were synthesized. All compounds were evaluated for their in vitro cytotoxicities in four human carcinoma cells (HepG2, MCF-7, HCT-116 and A549). Among them, compound 7l displayed the most potent cytotoxicity with an IC50 (concentration of the tested compound that inhibits 50% of cell growth) value of 7.37 ± 0.38 μM against MCF-7 cells. The preliminary cellular mechanism studies indicated that compound 7l could induce MCF-7 cells apoptosis. The above findings indicated that compound 7l may be used as a lead compound for antitumor agents with improved efficacy.

In this work, we found that polyethyleneimine (PEI), a widely applied organic high-molecular polymer, could act as a new co-reactant to obviously improve the electrochemiluminescence (ECL) of S2O82--O2 system. And owing to its abundant amine groups in the polymeric structure, PEI was further used to covalently crosslink with massive L-cysteine (L-Cys), an effective co-reactant of S2O82--O2 ECL system, to obtain a new co-reactive high-molecular polymer (PEI-L-Cys) with higher co-reaction efficiency. As loading platform, hierarchically branched Au/Pd dendrimers (Au/Pd DRs G2) were prepared to immoblize the obtained PEI-L-Cys, detection antibody, and bolocking reagent glucose oxidase (GOD). With the existence of target carcinoembryonicantigen (CEA), an ECL immunosensor was constructed through the sandwiched immunoreaction between the capture antibody on the electrode and the bioconjugate based on Au/Pd DRs G2. Besides the high enhancement of PEI-L-Cys, the ECL signal was also greatly increased by the dual catalysis to generate O2 in situ around the electrode induced by the synergistic effect of GOD and Au/Pd DRs G2 in presence with D-glucose. Especially, due to the special hierarchically branched bimetallic structure, the Au/Pd DRs G2 had more excellent catalytic effect to H2O2 decomposition in this process. As a result, the proposed ECL immunosensor realized the ultrasensitive detection of CEA, which could provide meaningful reference to the prevention and treatment of related disease.

Seven new steroidal 5α,8α-endoperoxide derivatives with C-17 aromatic hydrazone side chain were synthesized. Structures of the synthesized compounds were characterized by IR, 1H NMR, 13C NMR, and mass spectrometry. Anti-proliferative activities of the synthesized compounds were evaluated in vitro by the MTT method. Among the seven compounds, 5α,8α-epidioxy-17-(4-chloro-benzylidene)-hydrazonoandrost-3β-ol showed the strongest anti-proliferative activity against three human cancer cell lines (MCF-7, HepG2, and SK-Hep1).

Two new series of betulin derivatives with semicarbazone (7a–g) or thiosemicarbazone (8a–g) groups at the C-28 position were synthesized. All compounds were evaluated for their in vitro cytotoxicities in human hepatocellular carcinoma cells (HepG2), human breast carcinoma cells (MCF-7), human lung carcinoma cells (A549), human colorectal cells (HCT-116) and normal human gastric epithelial cells (GES-1). Among these compounds, 8f displayed the most potent cytotoxicity with an IC50 value of 5.86 ± 0.61 μM against MCF-7 cells. Furthermore, the preliminary mechanism studies in MCF-7 cells showed that compound 8f could trigger the intracellular mitochondrial-mediated apoptosis pathway by losing MMP level, which was related with the upregulation of Bax, P53 and cytochrome c expression, the downregulation of Bcl-2 expression, activation of the expression levels of caspase-3, caspase-9, cleaved caspase-3 and cleaved caspase-9, and an increase in the amounts of intracellular reactive oxygen species. These results indicated that compound 8f may be used as a valuable skeleton structure for developing novel antitumor agents.

Piezoelectric nanosensors were prepared with a novel type of dehydrofluorinated poly(vinylidene fluoride) (PVDF) nanofibrous membrane. With the synergistic effect of the dehydrofluorination reaction and applied high voltage electric field, the piezoelectric and energy storage properties of fibrous membranes attained great improvement. It was found that the simultaneous introduction of conjugated double bonds to the backbone of PVDF which was accompanied with the elimination of HF, resulted in the decrease of its molecular weight, solution viscosity and hydrophobicity. The crystalline phase, diameter, piezoelectric and energy storage properties of electro-spun PVDF nanofiber membranes significantly depend on the degree of HF elimination in dehydrofluorinated PVDF. The dehydrofluorinated PVDF with 5 hours of reaction exhibits the highest discharged energy density (Wrec) and energy storage efficiency (η), but excessive dehydrofluorination reaction is unfavorable to the energy storage properties. In addition, the dehydrofluorinated PVDF fiber membrane-based nanosensor possesses a larger electrical throughput (open circuit voltage of 30 V, which is three time that of the untreated PVDF), indicating that the introduction of double bonds can also improve the piezoelectric properties of PVDF nanofibers.

A water-resistant polyamide-oxidized starch-methyl methacrylate (P-OS-M) adhesive with zero formaldehyde-emission was successfully synthesized, using natural corn starch, KMnO4, polyamide and methyl methacrylate as raw material, oxidant, crosslinking agent and comonomer, respectively. The P-OS-M25 adhesive synthesized with the optimal amount of methyl methacrylate (25 ml) could reach wet shear strength of 1.04 MPa, which was far greater than natural starch (NS) and oxidized starch (OS). Fourier transforms infrared spectrometer (FTIR) and X-ray diffraction (XRD) results showed that polyamide and methyl methacrylate were successfully cross-linked and copolymerized with oxidized starch. In addition, thermogravimetric analysis (TGA), rheology, scanning electron microscope (SEM) and contact angle respectively indicated that P-OS-M adhesive was suitable for wood adhesives in terms of thermal stability, viscosity, morphological and water resistence. These advantages increased the possibility of P-OS-M adhesive instead of petroleum-based wood adhesives.

Background Solid tumor hypoxic conditions prevent the generation of reactive oxygen species (ROS) and the formation of DNA double-strand breaks (DSBs) induced by ionizing radiation, which ultimately contributes to radiotherapy (RT) resistance. Recently, there have been significant technical advances in nanomedicine to reduce hypoxia by facilitating in situ O2 production, which in turn serves as a “radiosensitizer” to increase the sensitivity of tumor cells to ionizing radiation. However, off-target damage to the tumor-surrounding healthy tissue by high-energy radiation is often unavoidable, and tumor cells that are further away from the focal point of ionizing radiation may avoid damage. Therefore, there is an urgent need to develop an intelligent targeted nanoplatform to enable precise enhanced RT-induced DNA damage and combined therapy. Results Human epidermal growth factor receptor 2 (Her2)-specific dimeric affibody (ZHer2) mediated cisplatin-loaded mesoporous polydopamine/MnO2/polydopamine nanoparticles (Pt@mPDA/MnO2/PDA-ZHer2 NPs) for MRI and enhanced chemo-radiotherapy of Her2-positive ovarian tumors is reported. These NPs are biodegradable under a simulated tumor microenvironment, resulting in accelerated cisplatin release, as well as localized production of O2. ZHer2, produced using the E. coli expression system, endowed NPs with Her2-dependent binding ability in Her2-positive SKOV-3 cells. An in vivo MRI revealed obvious T1 contrast enhancement at the tumor site. Moreover, these NPs achieved efficient tumor homing and penetration via the efficient internalization and penetrability of ZHer2. These NPs exhibited excellent inhibition of tumor growth with X-ray irradiation. An immunofluorescence assay showed that these NPs significantly reduced the expression of HIF-1α and improved ROS levels, resulting in radiosensitization. Conclusions The nanocarriers described in the present study integrated Her2 targeting, diagnosis and RT sensitization into a single platform, thus providing a novel approach for translational tumor theranostics. Graphic abstract

A new polyoxometalate-based coordination polymer, Ag2(L)2(VW12O40)][Ag2(L)2]·4H2O (1) {L = 3,5-di(1H-1,2,4-triazol-1-yl)benzoic acid}, has been isolated under hydrothermal conditions and characterized by routine methods. Compound 1 exhibits an interesting 1D + 1D polypseudo-rotaxane architecture, as shown by X-ray diffraction analysis. The new compound represents a scarce example of 1D + 1D polypseudo-rotaxane architecture, namely, ladder motifs are threaded by zigzag chains rather than a straight one. The coordination stability around loop and thread motifs was investigated to expatiate on the zigzag chained polypseudo-rotaxane. In addition, crystal 1 can be used as a packing material to selectively adsorb cationic dyes such as crystal violet (CV) and methylene blue (MB) concomitant with methyl orange anionic dyes with high uptakes and rapid adsorption rate.

Here, we fabricated a novel photoelectrochemical (PEC) aptasensor based on Br,N-codoped TiO2/CdS quantum dots (QDs) sensitization structure with excellent energy level arrangement for supersensitiv...

MoS2 catalysts with abundant S and Mo defects have been developed for the one-pot reductive amination of nitro compounds with aldehydes to synthesize secondary amines. The combination of multiple s...

Furfural (FAL) is one of the most important biomass-derived platform compounds. The catalytic transformation of FAL was investigated with three porous Zr–thiophenedicarboxylate hybrids for the production of furfuryl alcohol (FOL). Three Zr-based catalysts, including DUT-67(Zr), DUT-68(Zr) and DUT-69(Zr) were synthesized through a facile assembly of 2,5-thiophenedicarboxylate acid with ZrCl4 using the acetic acid as a modulator under hydrothermal conditions. These catalysts were also characterized using FT-IR, XRD, SEM, TEM, N2 adsorption–desorption, XPS and TG. The specific surface area of the DUT-69(Zr) is smaller than that of the DUT-68(Zr) and slightly larger than that of the DUT-67(Zr), but it has a relatively large pore volume and pore diameter. Although all three catalysts showed excellent catalytic activity towards the catalytic transfer hydrogenation of FAL into FOL, the DUT-69(Zr) material has slightly higher catalytic activity than the other two catalysts. Besides, considering the cost of catalyst preparation, the DUT-69(Zr) material was used as the optimal catalyst and studied in detail. A high FOL yield of 92.2% at 95.9% FAL conversion was achieved at 120 °C for 4 h over DUT-69(Zr). Meanwhile, the DUT-69(Zr) could be reused more than six times with a minor decrease in catalytic activity. Finally, a plausible mechanism for catalytic transfer hydrogenation of carbonyl compounds to produce corresponding alcohols was presented based on the results of the experiments and previous reports.

Porcine epidemic diarrhea (PED) which is caused by porcine epidemic diarrhea virus (PEDV), is an intestinal communicable disease. In recent years, though pigs have been immunized with the vaccines in pig farms, PED still broke out and caused severe economic losses to the swine industry in the northeast China. In this study, the sample was positive for PEDV variant strains via the nano-nest PCR. The strain was successfully isolated from positive samples and was serially passaged in Vero-E6 cells. In addition, the strain was identified via electron microscopy observation, indirect immunofluorescence assay and infection experiment in newborn piglets and named PEDV CH/JLDH/2016 strain (Accession No. MF346935). Phylogenetic analysis of the S gene showed that the CH/JLDH/2016 strain was clustered into G2b subgroup. Comparing with the CV777 vaccine strain, amino acid sequence analysis of CH/JLDH/2016 strain showed that 15 nucleotides were inserted and 9 were absent in S gene, whose amino acid sequence it educed insertions of 5 amino acids(58NQGX61 and 145N) and absences of 3 amino acids(164RD165 and 1204Y). Our strain, in the SS2 epitope have no amino acid, variant while in SS6 epitope, Y changed into S in 776th amino acid. The results indicated that PEDV G2b variant strains have been emerged in Jilin province. The identification of new types of PEDV variant strains would stimulate the development of effective vaccines for the prevention and control of PED. The novel vaccines that based on these newly identified PEDV variant strains may contribute to the control of PED outbreaks in China., Highlights • The isolated variant PEDV from Dehui, China, was distributed into the G2b subgroup. • The differences of strains help to explain why PEDV vaccines have no protection in most piglets in China. • Our variant PEDV with the absence of Y in the 776th aa was from G2b subgroup while others were from G1a subgroup.

In this study, we developed novel thermal and redox-responsive micelles based on the Pluronic F127 tri-block copolymer and employed these for redox-responsive intratumor release of bufalin, an anti-cancer drug. Pluronic F127 was first functionalized with carboxylate groups, and then assembled into micelles. The HOOC-F127-COOH micelles are 20 ± 4 nm in size at 37 °C, but expand to 281 ± 5 nm when cooled to 4 °C. This allows for the free diffusion of bufalin into the micellar cores at low temperatures, while at 37 °C the micelles are much more compact and the drug molecules can be effectively held in their interiors. A high encapsulation efficiency and loading content were obtained via drug incorporation at 4 °C. The drug-loaded micelles were cross-linked with cystamine, which contains a disulfide bond responsive to the local cancer microenvironment. In vitro studies showed that drug release from the cross-linked micelles was low under normal physiological conditions, but markedly accelerated upon exposure to conditions representative of the intracellular tumor environment. Confocal microscopy revealed that the cross-linked micelles gave high levels of drug release inside the cells. In vivo studies in mice showed the drug-loaded cross-linked micelles have potent anti-tumor activity, leading to high levels of apoptosis of tumor cells and significant reductions in tumor volume. The drug-loaded cross-linked micelles did not significantly influence body weight, and there was no evidence for detrimental off-target effects. These results indicate that the Pluronic-based micelles developed in this work are promising drug delivery systems for the targeted treatment of cancer.

In this work, effects of 10 keV argon ion implantation on laser-induced damage threshold (LIDT) of fused silica were systematically investigated with ion fluences ranged from 1 × 1016 ions/cm2 to 1 × 1018 ions/cm2. Results show that only when the ion fluence increases above 1 × 1017 ions/cm2, the surface roughness apparently increases due to the formation of argon bubbles in the surface of fused silica. The concentration of defects decreases with the increased fluences up to 1 × 1017 ions/cm2 but then increases further, especially for the oxygen deficient center (ODC) defect. Based on the nanoindentation test results, Ar ion implantation generates large compressive stress and strengthens the surface of fused silica by surface densification. With the increase of the Ar ion fluences, the LIDTs of the samples increase due to the increases in both surface compressive stress and defects annihilation. However, at higher ion fluences, the increase of the densities of defects and argon bubbles are identified as the key reasons for the decrease of the LIDTs. Therefore, Ar ion implantation can improve the LIDTs of fused silica at moderate fluences.

A class of π-extended BF2 β-diketone chromophores, ADBF2-a and ADBF2-b, that containing electron donating N-butyl acridone units have been synthesized. ADBF2-a and ADBF2-b are highly fluorescent with quantum efficiencies (ΦF) close to unity in toluene. The fluorescence of ADBF2-b displays more pronounced solvatochromism and shows a twisted intramolecular charge transfer (TICT) character in polar solvent and aggregation induced emission enhancement (AIEE) behavior. Furthermore, ADBF2-b shows high contrast and sensitive acid/base induced emission “On/Off” switching that result from the reversible protonation/deprotonation of the nitrogen atom. The compounds are also highly luminescent in solid state with a ΦF value of 0.63 for ADBF2-a and 0.28 for ADBF2-b. Single crystal analysis reveals the highly rigid and planar backbone of ADBF2-a. The emission stimuli-responsive properties of the compounds in solid state have been investigated. ADBF2-a shows yellow emission (λem = 564 nm) in crystalline state while turned to be orange (λem = 586 nm) after grinding. Intriguingly, CH2Cl2 vapor fuming of the ground solid led to red emissive (λem = 624 nm) solid, which turned to original yellow color with further CH2Cl2 vapor fuming. The solid of ADBF2-b emits red (λem = 645 nm) fluorescence in crystalline state and red-shifted to λem = 680 nm for amorphous solid after mechanical grinding. The crystalline state was recovered by CH2Cl2 vapor fuming. We believe that this BF2 system will inspire the development of high luminescent solid-state materials, and provide important insights into smart stimuli-responsive properties.

A novel catalyst, Zr(IV)-salen-MCM-41 with Lewis acid and base sites, was prepared and characterized by FT-IR, TG, XRD, SEM, TEM, BET, NH3-TPD, and CO2-TPD. The as-synthesized catalyst was applied to the conversion of fructose into 5-hydroxymethylfurfural (HMF). In this work, the heterogeneous catalyst had a superior activity for the dehydration of fructose into HMF. 92.0% HMF yield was obtained from fructose at 140 °C for 4 h in dimethyl sulfoxide (DMSO). In addition, the effect of reaction temperature, reaction time, solvents and catalyst dosages were also investigated in detail. Meanwhile, the Zr(IV)-salen-MCM-41 could be reused four times with a slight decrease in catalytic activity

A ladder-type π-system PDIPY that bearing perylene diimide and pyrene units have been developed for constructing non-fullerene acceptors. The vinyl bridged PDIPY dimer PDIPY-V and polymer PPDIPY-V have been synthesized via bromonation and Stille coupling recation. PDIPY-V and PPDIPY-V exhibit intense and broad absorption within 400–650 nm that complement the absorption spectra of the narrow bandgap polymeric donors. DFT calculation indicated that PDIPY-V and PPDIPY-V hold highly twisted structure, which prevent the formation of π−π stacking and crystallization in the aggregated states. The grazing-incidence wide-angle X-ray scattering (GIWAXS) and atomic force microscopy (AFM) investigations confirmed the amorphous nature of the pure films and the PDIPY-V/PPDIPY-V:PTB7-Th blend films. The PDIPY-V:PTB7-Th based photovoltaic device showed a poor performance due to the small LUMO offset of donor and acceptor. While the PPDIPY-V:PTB7-Th based device showed a high PCE of 5.20%, indicating the PDIPY derivatives are promising non-fullerene acceptors for polymer solar cells.

As the effect of aerosol on the atmosphere is related to its hygroscopic properties, it is desirable to know the microscopic mechanism for the interaction between water and the aerosol consisting of inorganic and organic ingredients. In this work, molecular dynamics method is employed to investigate the behavior of formic acid - water systems without or with sodium chloride (NaCl), which represent simplified typical atmospheric aerosols. It mainly focuses on the effects of temperature, humidity and NaCl concentration on the structure and the interfacial properties of the aerosol at different simulation times. The results show that when the simulation time is 2 ns, with the increase of temperature the binary aggregate containing 360 H2O displays the demixed structure 1 (water clusters adsorb on the acid aggregate), the mixed structure (water molecules dissolve part of the acid aggregate) and the demixed structure 2 (acid molecules uniformly wrap around the water core). The stability of formic acid particles increases with the increase of NaCl concentration. Hence, the ternary aggregate containing 20 NaCl presents three identical structures, while only the first two structures can be observed for the ternary aggregate with 40/80 NaCl. At the equilibrium state, all three structures can be found in each aggregate containing 360 H2O, while the difference in structure can only be observed at intermediate temperatures. Correspondingly, only the first two structures are evidenced for all aggregates containing 120 H2O at the time of 2 ns and the equilibrium state. Hydrogen atoms (H(C H)) of the formic acid at the surface of all aggregates point toward the gas phase. Moreover, the ratio of organic molecules to inorganic molecules at aerosol surface increases with the increase of temperature and the decrease of NaCl and water content. Finally, the hygroscopic properties of the studied aerosols are discussed.

In this work, a novel ternary Ag@Ag2O/BiOCl Z-scheme photocatalyst driven by visible light was successfully fabricated through a simple two-step route in which the Ag@Ag2O cocatalyst was decorated on {001} crystal facets of BiOCl nanosheets. As controls, BiOCl nanosheet, Ag2O nanoparticle and Ag/BiOCl composite were also synthesized by the appropriate means. The as-synthetized samples were investigated by various characterization methods. Compared with the pristine BiOCl, Ag2O and Ag/BiOCl counterparts, the Ag@Ag2O/BiOCl composite exhibited a superior performance towards RhB degradation with an efficiency of 91.2% within 120 min under visible light illumination of which the reaction rate is about 32, 3 and 5 times as much as pristine BiOCl, Ag2O and Ag/BiOCl samples, respectively. The enhanced performance for RhB degradation may be ascribed to a possible Z-scheme junction, which is advantageous to effectively boost interfacial charge transport and depress the photoinduced carrier recombination. The detailed Z-scheme mechanism towards RhB degradation of the Ag@Ag2O/BiOCl composite was also further explored and discussed.