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A novel and recoverable platform of polyurethane (PU) sponge-supported Au nanoparticle catalyst was obtained by a water-based in-situ preparation process. The structure, chemical, and morphology properties of this platform were characterized by XRD, TGA, SEM, FT-IR, and XPS. The Au/PU sponge platform exhibited excellent catalytic performances in catalytic reductions of p-nitrophenol and o-nitroaniline at room temperature, and both catalytic reactions could be completed within 4.5 and 1.5 min, respectively. Furthermore, the strong interaction between Au nanoparticles and the PU sponge enabled the catalyst system to maintain a high catalytic efficiency after 5 recycling times, since the PU sponge reduced the trend of leaching and aggregation of Au nanoparticles. The unique nature of Au nanoparticles and the porous PU sponge along with their strong interaction resulted in a highly efficient, recoverable, and cost-effective multifunctional catalyst. The AuNP/Sponge nanocatalyst platform has great potential for wide environmental and other catalytic applications.

This work investigated the electrochemical degradation of amoxicillin (AMX) in aqueous solution with Cu-PbO2 electrode. The main influence factors on the degradation of AMX, such as Na2SO4 concentration, initial AMX concentration, current density and initial pH value, were analyzed in detail. Under the optimal conditions, the removal rates of AMX and chemical oxygen demand (COD) reached 99.4% and 46.3% after 150 min treatment. The results indicated that the electrochemical degradation of AMX fitted pseudo-first-order reaction kinetics. Compared with undoped PbO2 electrode, Cu-PbO2 electrode had a smaller crystal size, more proportion of hydroxyl oxygen species, greater AMX and chemical oxygen demand (COD) removal efficiency, higher average current efficiency (ACE) and lower electrical efficiency per log order (EE/O). Electrochemical oxidation using Cu-PbO2 electrodes was an effective way to eliminate amoxicillin in aqueous solution. Moreover, a possible degradation pathway including ring open and mineralization was proposed by intermediate products determined by GC-MS method. This paper could provide basic data and technique reference for the amoxicillin wastewater pollution control.

The biological function of the natural ent-kaurene diterpenoid isolated from genus Isodon, oridonin, has been intensively studied. However, its mechanism studies and clinical applications were hampered by its moderate biological activities. In order to enlarge the applied range of oridonin and explore its mechanism of action, a series of derivatives were designed and synthesized based on the structure of oridonin. Some of the derivatives were significantly more potent than oridonin against four cancer cell lines. Especially, the most potent compound 20 markedly inhibited the proliferation of well differentiated HepG2 and poorly differentiated PLC/PRF/5 cells, with IC50 values as low as 1.36 μM and 0.78 μM respectively, while the IC50 values of oridonin are 8.12 μM and 7.41 μM. We found that compound 20 inhibited liver cancer cell proliferation via arresting cell cycle at G1 phase. Moreover, it induced liver cancer cell apoptosis by decreasing the mitochondrial membrane potential, increasing intracellular reactive oxygen species level and inducing the expression of apoptosis-related proteins. Furthermore, compound 20 significantly inhibited growth of PLC/PRF/5 xenograft tumors in nude mice and had no observable toxic effect. Altogether, these results indicated that compound 20 is a promising lead for liver cancer therapeutics.

A series of TiO2 catalyst carriers with ceria additives were prepared by a precipitation method and tested for selective catalytic reduction (SCR) of NO by NH3. These samples were characterized by XRD, N2-BET, NH3-TPD, H2-TPR, TEM, XPS and in situ DRIFTS, respectively. Results showed that the appropriate addition of ceria can enhance the catalytic activity and thermostability of TiO2 catalyst carriers significantly. The maximum catalytic activity of Ti-Ce-Ox-500 is 98.5% at 400 °C with a GHSV of 100 000 h−1 and the high catalytic activity still remains even after the treatment at high temperature for 24 h. The high catalytic performance of Ti-Ce-Ox-500 can be attributed to a series of superior properties, such as larger specific surface area, more Bronsted acid sites, more hydrogen consumption, and the higher proportion of chemisorbed oxygen. Ceria atoms can inhibit the crystalline grain growth and the collapse of small channels caused by high temperatures. Furthermore, in situ DRIFTS in different feed gases show that the SCR reaction over Ti-Ce-Ox-500 follows both E-R and L-H mechanisms.

Because oral transmission of SARS-CoV-2 is 3-5 orders of magnitude higher than nasal transmission, we investigated debulking of oral viruses using viral trap proteins (CTB-ACE2, FRIL) expressed in plant cells, delivered through the chewing gum. In omicron nasopharyngeal (NP) samples, the microbubble count (based on N-antigen) was significantly reduced by 20 μg of FRIL (p 0.0001) and 0.925 μg of CTB-ACE2 (p = 0.0001). Among 20 delta or omicron NP samples, 17 had virus load reduced below the detection level of spike protein in the RAPID assay, after incubation with the CTB-ACE2 gum powder. A dose-dependent 50% plaque reduction with 50-100 ng FRIL or 600-800 μg FRIL gum against Influenza strains H1N1, H3N2, and Coronavirus HCoV-OC43 was observed with both purified FRIL, lablab bean powder or gum. In electron micrographs, large/densely packed clumps of overlapping influenza particles and FRIL protein were observed. Chewing simulator studies revealed that CTB-ACE2 release was time/dose-dependent and release was linear up to 20 min chewing. Phase I/II placebo-controlled, double-blinded clinical trial (IND 154897) is in progress to evaluate viral load in saliva before or after chewing CTB-ACE2/placebo gum. Collectively, this study advances the concept of chewing gum to deliver proteins to debulk oral viruses and decrease infection/transmission.

Geometric information and discontinuity characterization of rock masses are the key aspects of the analysis of the evolution and failure mechanisms of rockfalls. With the advantageous use of terrestrial laser scanning (TLS), the accurate three-dimensional (3D) spatial information of rock slopes can be obtained without contact. By conducting a fuzzy K-means algorithm in this study, the automatic identification of discontinuity sets is achieved, and dominant occurrences of rock mass discontinuities in each local region can be acquired in great detail. This automatic identification method permits the user to visually identify the discontinuity sets and acquire their spacial distribution features, e.g. occurrences, spacings, trace lengths and their geometric compounding relationships. At the same time, based on the shortest distance (SD) algorithm and the surface-to-plane volume calculation algorithm, the distributions, shapes, volumes and scars of the rockfalls can be accurately detected over the monitored time interval. These methods are able to provide adequate investigations and quantitative assessment for the rockfall failure mechanisms and evolutions of the Hongshiyan post failure rock slope after the 2014 Ludian earthquake. The topography of the landslide surface, mechanical properties, scales and the structural features of the discontinuities have a significant effect on the failure mechanisms, distributions and volumes of rockfalls. The main failure mechanisms of the rockfall investigated in this rock slope can be divided into plane failure, wedge failure and toppling failure. The plane and wedge failures mainly occurred in the landslide surface while the toppling failures are mainly observed along the edge of the post failure slope, which is obviously responded by preferred discontinuities. The reverse-dip stratified structure characteristics and the excavation disturbances during the recovering and slope treatment stage induce numerous progressive and continuous failures of rockfalls. The results are beneficial for the design and optimization of rockfall treatments.

Conventional systematically-administered drugs distribute evenly throughout the body, get degraded and excreted rapidly while crossing many biological barriers, leaving minimum amounts of the drugs at pathological sites. Controlled drug delivery aims to deliver drugs to the target sites at desired rates and time, thus enhancing the drug efficacy, pharmacokinetics, and bioavailability while maintaining minimal side effects. Due to a number of unique advantages of the recent microfluidic lab-on-a-chip technology, microfluidic lab-on-a-chip has provided unprecedented opportunities for controlled drug delivery. Drugs can be efficiently delivered to the target sites at desired rates in a well-controlled manner by microfluidic platforms via integration, implantation, localization, automation, and precise control of various microdevice parameters. These features accordingly make reproducible, on-demand, and tunable drug delivery become feasible. On-demand self-tuning dynamic drug delivery systems have shown great potential for personalized drug delivery. This review presents an overview of recent advances in controlled drug delivery using microfluidic platforms. The review first briefly introduces microfabrication techniques of microfluidic platforms, followed by detailed descriptions of numerous microfluidic drug delivery systems that have significantly advanced the field of controlled drug delivery. Those microfluidic systems can be separated into four major categories, namely drug carrier-free micro-reservoir-based drug delivery systems, highly integrated carrier-free microfluidic lab-on-a-chip systems, drug carrier-integrated microfluidic systems, and microneedles. Microneedles can be further categorized into five different types, i.e. solid, porous, hollow, coated, and biodegradable microneedles, for controlled transdermal drug delivery. At the end, we discuss current limitations and future prospects of microfluidic platforms for controlled drug delivery.

Based on the pyrolysis of zeolitic imidazolate framework-67/Ni-Co layered double hydroxide (ZIF-67/Ni-Co LDH) precursor, we successfully prepare a novel Co3O4/NiCo2O4@NC double-shelled hollow structure catalyst. After carbonization, Co3O4/NiCo2O4@NC inherit the polyhedral shape from ZIF-67/Ni-Co LDH. At the same time, obvious inter-shell pores appear between the inner shell and outer shell of Co3O4/NiCo2O4@NC. Compared with simple single-shell Co3O4@NC catalyst, more complex hollow structure brings better electrochemical performance of the material. Co3O4/NiCo2O4@NC modified graphite felt (GF) electrode is used to degrade levodopa in Electro-Fenton (EF) system. According to the experimental results, the removal rate of levodopa and TOC have reached 99.07% and 60.16%, respectively after 2 h reaction. The EF reaction for the degradation of levodopa follows a pseudo first-order kinetic model. Based on the intermediate product, we propose a possible degradation pathway of levodopa. In addition, we have evaluated the reusability of Co3O4/NiCo2O4@NC-GF electrode in EF reaction. Finally, we believe that the Co3O4/NiCo2O4@NC-GF electrode is a promising cathode for the treatment of pharmaceutical wastewater in EF field.

Novel rhodamine and quinoline-functionalized nano film was prepared by copolymerization and electrospinning. Propenyl monomer of rhodamine and quinoline was synthesized and then copolymerized with methyl methacrylate via solution polymerization. This prepared copolymer was electrospun into nano film, as a solid-state sensor, which exhibits highly selective recognition of Fe3+ ions over various environmentally and biologically relevant metal ions and anions with a distinct color change from colorless to pink in very fast response time (

A novel 1,8-naphthalimide-based chemosensor was designed and synthesized for rapid recognition of Cr 3+ . The desired sensor showed off-on fluorescent and lifetime-based response upon Cr 3+ and S 2− in solution, on test paper and in cells. With the intensity-based method, the limit of quantification (LOQ) value was 0–5.5 × 10 −5 M and the detection limit could be as low as 0.60 ppm. The ' in situ ' prepared Cr 3+ complex can recognize S 2− among a series of common anions with high selectivity and sensitivity, the LOD can be as low as 307 nM. The lifetime of the sensor changes from 4.95 to 4.89 and further to 5.88 ns upon addition of Cr 3+ and S 2− in turn.

In this study, the CNTs were successfully compounded in PbO2 electrode through composite electrodeposition technology to obtain multi-layer CNT-PbO2 electrode. Scanning electron microscope, X-ray diffraction and X-ray Photoelectron Spectroscopy were comprehensively used to characterize the lead dioxide electrode and the electrochemical performance were also tested by cyclic voltammetry, and electrochemical impedance spectroscopy. Results showed that CNT-PbO2 significantly improved the electrochemical performance, which was attributed to that the compound of CNTs in PbO2 improved the active sites on the surface, with higher oxidation peaks, smaller particle size, larger specific surface area, and lower charge transfer resistance. In the degradation experiment, the chemical oxygen demand removal efficiency of isoniazid by CNT-PbO2 electrode were 1.37 times of that by pure PbO2 electrode. The main influence factors on the degradation of ISN, such as initial ISN concentration, Na2SO4 concentration, current density and initial pH value was analyzed in detail. Considered comprehensively the effects of ISN removal efficiency, COD and average current efficiency, the degradation of ISN and COD reached 99.4% and 86.8%, respectively, after the electrode was degraded by electrochemical oxidation for 120 min under the best conditions. In addition, the degradation mechanism of ISN in electrochemical oxidation was studied. According to the intermediate products detected by GC-MS, the possible degradation pathway of ISN in electrochemical oxidation system were proposed.

In this study, Cu doped PbO2 electrode was prepared by electrodeposition and used for electrochemical oxidation degradation of amoxicillin (AMX), which showed that the effect of Cu doped PbO2 electrode was better than that of undoped PbO2 electrode in degrading amoxicillin. An optimized model was setup with the help of response surface method (RSM). The optimal values of experimental parameters and the interactions between the parameters were explored, including current density, pH and initial AMX concentration. The combustion efficiency was calculated in the electrochemical oxidation of amoxicillin in aqueous solution and the enhancement was found with Cu doped PbO2 electrode. The enhanced mechanism with Cu doped PbO2 electrode was discussed based on the analysis of hydroxyl radicals and the combustion efficiency. The mechanism of amoxicillin degradation was discussed. This paper can provide basic data and technique reference for amoxicillin pollution control.

A novel indium (In) doped PbO2 electrode featuring high electrochemical activity and electrode stability toward electrochemical degradation of refractory organic pollutants was prepared by electrodeposition technique. Based on the aspirin removal efficiency, the optimized molar ratio of In/Pb in electrodeposition solution was 1%. In contract with the undoped PbO2 electrode, the constructed In-doped PbO2 electrode displayed a more compact structure, a better oriented crystal of smaller size, an increased concentration of active oxygen species, a higher oxygen evolution potential, a lower charge transfer resistance and a higher electrode stability. The In-doped PbO2 electrode was demonstrated to have a superior electrochemical oxidation ability with higher OH generation capacity. For In-doped PbO2 electrode, the removals of aspirin and COD reached 76.45% and 52.09% after 2.5 h of electrolysis, respectively. Meanwhile, the energy saving could be up to 30.56% after In doping. This outcome was in good agreement with the results of surface characterization of PbO2 electrodes. Finally, combination with the safety evaluation, we could conclude that In-doped PbO2 electrode was a promising anode for the treatment of organic pollutants.

Based on hydrolysis reaction by Cu2+ and intermolecular hydrogen bond, a dual functional colorimetric probe, a novel 1,8-naphthalimide derivative was designed and synthesized for Cu2+ and F− naked-eye recognition with high sensitivity and excellent selectivity. The probe can detect Cu2+ and F− quantitatively in concentration range of 0–16.7 μM and 0–23.3 μM, and the detection limit could be as low as 370 nM for Cu2+ and 720 nM for F−. The detection of F− on chromatography plates and the preliminary application of 1 to detect fluorine contents in several kinds of toothpaste, tap water and Eyebrow Lake have been successfully demonstrated.

A dual-model fluorescent probe for formaldehyde has been developed. With excitation at 365 and 400 nm respectively and upon addition of formaldehyde, the fluorescent probe displays off-on fluorescence responses at 415 and 505 nm. Formaldehyde can be detected quantitatively in the concentration range from 0 to 2.7 × 10 −2 M and the detection limit on fluorescence response of the probe can be as low as 6 μM. The proposed method was successfully employed for preliminary application in several commercially available foods.

Based on Rhodamine B, two Al 3þ /Cu 2þ -selective chemosensors were synthesized, which display a high selectivity for Al 3þ and Cu 2þ among environmentally and biologically relevant metal ions. A 1,8Naphthyridine modified rhodamine derivative can detect Al 3þ in ethanol with offeon fluorescence behavior, and detect Cu 2þ in aqueous solution with colorimetric method. The 8-Hydroxyquinoline-based rhodamine sensor can detect Al 3þ in ethanol with both offeon fluorescence and colorimetric methods. The detection mechanism involves a ring-opening process as a consequence of metal complex formation. Job’s plots and a time-of-flight mass spectral study indicated that each chemosensor chelated Al 3þ /Cu 2þ with 1:1 stoichiometry. The binding of the chemosensors and Al 3þ /Cu 2þ is chemically reversible by the addition of F � /EDTA solution, respectively.

Compared with other fluorescent probes, ratiometric fluorescence responses are more attractive because the ratio between the two emission intensities can be used to measure the analyte concentration and provide a built-in correction for environmental effects. A highly selective and sensitive ratiometric fluorescent probe for Fe 3+ was synthesized, which exhibits an enhanced fluorescence with a large red-shift in emission from 361 to 455 nm upon addition of Fe 3+ . The red-shift of the emission peak can be ascribed to the reformed orbital, and the increase of emission intensity may be ascribed to the inhibition of the rotation of C–C bonds between each two aromatic rings.

The zinc oxide whiskers were synthesized by the equilibrium gas expanding method at the temperature of 700 °C with metallic zinc as the main raw material without any catalysts. The effects of the growth time on microstructure and photoluminescence properties were investigated. The results show that the as-grown samples are composed of uniform tetrapod-like ZnO whiskers. The length and diameter of the arms of the tetrapod-like ZnO whiskers increase obviously with the increase of the growth time. The strong single ultraviolet (UV) emission centering 385-391 nm without any accompanying deep-level emission is observed in the room temperature photoluminescence (PL) spectra of the whiskers. The intensity of UV emission increases markedly with the increase of growth time.

Two new complexes, {[Cd(bimt)(bdc)(H2O)]·2H2O}n (1) and [Cd(bimt)(Hbtc)]n (2) have been synthesized through the self-assembly of Cd(NO3)2·4H2O with unsymmetrical N-heterocyclic ligand 2-((benzoimidazol-yl)methyl)-1H-tetrazole (bimt) and aromatic polycarboxylate acid 1,3-benzenedicarboxylic acid (H2bdc) or 1,3,5-benzenetricarboxylic acid (H3btc). Single crystal X-ray diffraction determination shows that complex 1 possesses an infinite 2-D layered structure with parallelogram grid units. Complex 2 is a 2-D layered structure containing 1-D ladder-like chains linked by the Hbtc2− anions in tridentate bridging fashion. Both complexes are stacked into complicated 3-D frameworks by coordinating bonds and hydrogen bonds in the solid state. In addition, the luminescent properties of both complexes have been investigated in the solid state at room temperature.

Four ferrocenyl complexes with the formulas {[Mn(η 2 -OOC(CH 2 ) 3 Fc) 2 (bbbm)]·CH 3 OH} n ( 1 ), {[Co(OOC(CH 2 ) 3 Fc)(η 2 -OOC(CH 2 ) 3 Fc)(bbbm)]·CH 3 OH} n ( 2 ), {[Ni(OOC(CH 2 ) 3 Fc) 2 (bbbm)(CH 3 OH) 2 ]·2CH 3 OH} n ( 3 ) and [Pb 6 (μ 2 -OOC(CH 2 ) 3 Fc) 2 (μ 3 -OOC(CH 2 ) 3 Fc) 2 (μ 2 -η 2 -OOC(CH 2 ) 3 Fc) 2 (η 2 -OOC(CH 2 ) 3 Fc) 2 (μ 4 -O) 2 ] ( 4 ) (Fc = (η 5 -C 5 H 5 )Fe(η 5 -C 5 H 4 ), bbbm = 1,1-(1,4-butanediyl)bis-1H-benzimidazole) have been synthesized and characterized by single crystal X-ray diffraction. Owing to the different conformations of the bbbm units in complexes 1 (or 2 ) and 3 , complexes 1 and 2 possess 1D helical chain structure with 2 1 screw axes along the b -direction, while complex 3 shows a 1D linear chain structure with ferrocenylbutyrate groups hanging on the chain. Complex 4 is a hexanuclear complex and exhibits a nano-scale wheel-like framework with six Pb(II) ions as a core and eight 4-ferrocenylbutyrate ligands as branches. The cyclic voltammetric studies show that the formal potentials of the four complexes are close to the free ferrocenylbutyrate ligand, which indicates that the coordination of the metal ions to the ferrocenyl ligand does not have significant effects on the redox potential of the ferrocenylbutyrate ligand. Further investigations suggest that the redox processes of the ferrocenylbutyrate ligand and complexes 1 – 4 are all chemically quasi-reversible processes and controlled by diffusion.

Two new complexes {[Co(bbbm)1.5(NO3)2]·H2O}n (1) and [Cd(bbbm)1.5(NO3)2]n (2) (bbbm = 1,1’-(1,4-butanediyl)bis-1H-benzimidazole) have been synthesized and structurally characterized. Both complexes are built up by two-dimensional coordination networks with (6, 3) nets. The third-order nonlinear optical (NLO) properties of the two complexes are determined and the results show that they not only possess large third-order NLO absorptive effects, but also display strong refractive behaviors. The hyperpolarizability |γ| values are 2.2 × 10−29 esu for complex 1, and 1.6 × 10−30 esu for complex 2. The NLO effective of complex 1 is stronger than that of 2 due to the decreased π back-donation capacity from Co(II) to Cd(II). Thermal analysis studies show that complex 1 is less stable and begins to decompose at 131 °C. While complex 2 is stable up to 257 °C.

The gene coding for glutathione S -transferase (GST) has been isolated from the Mytilus edulis hepatopancreas. Open reading frame analysis indicated that the M. edulis GST (meGST) gene encodes a protein of 206 amino acid residues with a calculated molecular mass of 23.68 kDa. The deduced amino acid sequence showed high sequence similarity with the sequence of the pi class GST. The meGST was expressed in Escherichia coli , and the recombinant meGST was purified by affinity chromatography and characterized. The recombinant meGST exhibited high activity towards the substrates ethacrynic acid (ECA) and 1-chloro-2,4-dinitrobenzene (CDNB). Kinetic analysis with respect to CDNB as substrate gave a K m of 0.68 mM and a V max of 0.10 mmol/min per mg protein. The recombinant meGST had a maximum activity at approximately pH 8.5, and its optimum temperature was 39 °C. The predicted three-dimensional structure of the meGST revealed the N-terminal domain possesses a thioredoxin fold and the six helices of the C-terminal domain make a α-helical bundle. These features indicate that the meGST belongs to pi class GST.