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In this paper, 3 mol% yttria-doped tetragonal zirconia polycrystal material (3 mol% Y2O3–ZrO2) was prepared using an optimised pressureless sintering process. The phase change and particle size distribution of Y2O3–ZrO2 during sintering were studied, and the effect of sintering temperature on the properties of Y2O3–ZrO2 was analysed. The raw materials and prepared samples were analysed using XRD, Raman spectroscopy, SEM, and Gaussian mathematical fitting. The results show that sintering encourages the transformation of the monoclinic phase into the tetragonal phase, thus improving the crystallinity of the sample. The relative content of the tetragonal phase in the sample increased from 57.43% to 99.80% after sintering at 1200 °C for 1 h. In the range of sintering temperatures studied in this paper (800–1200 °C), the zirconia material sintered at 1000 °C presented the lowest porosity and the best density.

Nanosized CeO2–ZrO2 powders prepared by atmospheric pressure pyrolysis were used as raw materials to prepare CeO2–ZrO2 ceramics using microwave sintering. The samples were characterised using bulk density measurements, X-ray diffraction (XRD), Fourier Transform Infrared Spectrometer (FT-IR), Raman, and scanning electron microscopy (SEM). The purpose was to determine the optimised microwave sintering process for CeO2–ZrO2 ceramics and reveal the corresponding mechanism. The results show that with a CeO2 addition content above 5 mol%, the tetragonal phase peak appeared obviously in the sample. The results show that the tetragonal phase peak appears when the CeO2 content is more than 5 mol%. The dopants, namely CeO2, have reduced the solid solution's phase transformation temperature with the assistance of microwave heating. Additionally, the grain size of the CeO2–ZrO2 ceramics has shown a negative relationship with Ce content at a temperature of 900 °C. The reason is that the rapid sintering due to microwave sintering and the oxygen vacancies generated by CeO2 can effectively inhibit grain growth. The regulation mechanism on microwave sintering of CeO2–ZrO2 ceramic was clarified, and the technical prototype of controlled prepared CeO2–ZrO2 ceramics by microwave sintering was constructed.

In this paper, the stability of CaO doped partially stabilised zirconia (CaO-PSZ) prepared by electrofusion method was improved from 88.14% to 95% within 1 h using the microwave heating method. The increase of the stability rate was because of the microwave heating method's advantages, including selective heating and fast heating. Analysis techniques, namely X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Raman spectroscopy, and scanning electron microscopy (SEM), were used to analysis the influences of the holding time (1–4 h) on the CaO doped PSZ samples at a heating temperature of 1100 °C to understand the fundamental mechanism of the optimisation process. The Raman and XRD spectra were fitted by the Gaussian method to further analysis the effect of holding time on the microstructure evolution of the samples. The fitting results indicated that the sample's crystal quality and stability were improved after microwave heating, and the optimised holding time is 2 h.

The effects of microwave power and sample quality on microwave drying kinetics and characteristics of zirconia were studied. It is found that by increasing the microwave power and decreasing the sample mass, the surface diffusion coefficient (Deff) appears to an upward tendency. The corresponding value Deff at a sample mass of 10, 20, 30, and 40g are 1.849E-14, 2.443E-14, 3.210E-14, and 3.278E-14 m2/s, respectively. The corresponding value Deff at a microwave power of 300, 400, 500, 600, and 700W are 1.270E-14, 1.784E-14, 2.619E-14, 3.392E-14, and 4.497E-14 m2/s, respectively. Besides, the materials were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FT-IR) to evaluate the changes of materials before and after drying. The results show that microwave accelerates the drying of zirconia and increases its dispersibility. The heat conduction direction of microwave drying is the same as that of moisture diffusion, which avoids being affected by heat inertia and heat transfer loss. The drying process is fast and efficient, and the microwave directly penetrates the product, avoiding the disadvantage of slow evaporation caused by the temperature gradient.

Vanadium pentoxide (V2O5) is one of the fundamental materials applied in the productions of batteries, vanadium-aluminium alloys, biomedicine, catalysis, etc. High purity V2O5 can be prepared from an intermediate product, namely ammonium polyvanadate (APV), using roasting after a drying process. In this paper, microwave heating was used as an alternative drying option for APV, which has advantages including selective heating, high heating efficiency, energy-saving, and environmental protection. The authors investigated the microwave heating characteristics of APV and discussed the effects of microwave power, the mass of APV, and initial water content on the efficiency of microwave drying. The dynamic analysis of the APV microwave drying process was also carried out. Four groups of thin-layer drying dynamic models, namely Modified-Page model, Verma model, Sickmplified-Fick's-diffusion model, and Two-term-exponential model, were fitted with the experimental data. Through comparison, the Modified Page model could better describe the microwave drying process of APV.

In the present study, controllable microwave sintering was applied to prepare partially stabilised zirconia ceramics with enhanced phase composition and a more uniform structure. To reveal the phase interface properties and structural changes of PSZ ceramics during the microwave sintering process, XRD, FT-IR, Raman, and SEM characterisations were utilised. XRD analysis and Raman analysis demonstrated that the increase of sintering temperature promoted the martensite conversion. However, prolonging duration time was unconducive to the retention of the stable phase. Additionally, the FT-IR characteristic peak movement caused by the reversible phase martensite transformation was observed. Furthermore, SEM analysis found that microwave treatment improved the grain size and structure distribution of the as-received MgO-PSZ sample. This work constructed a controllable technical prototype of preparing PSZ ceramics via microwave sintering, which can provide a theoretical basis and experimental basis for further industrial production.

Single-atom catalysts have attracted numerous attention due to the high utilization of metallic atoms, abundant active sites, and highly catalytic activities. Herein, a single-atom ruthenium biomimetic enzyme (Ru-Ala-C3N4) is prepared by dispersing Ru atoms on a carbon nitride support for the simultaneous electrochemical detection of dopamine (DA) and uric acid (UA), which are coexisting important biological molecules involving in many physiological and pathological aspects. The morphology and elemental states of the single-atom Ru catalyst are studied by transmission electron microscopy, energy dispersive X-ray elemental mapping, high-angle annular dark field-scanning transmission electron microscopy, and high-resolution X-ray photoelectron spectroscopy. Results show that Ru atoms atomically disperse throughout the C3N4 support by Ru-N chemical bonds. The electrochemical characterizations indicate that the Ru-Ala-C3N4 biosensor can simultaneously detect the oxidation of DA and UA with a separation of peak potential of 180 mV with high sensitivity and excellent selectivity. The calibration curves for DA and UA range from 0.06 to 490 and 0.5 to 2135 μM with detection limits of 20 and 170 nM, respectively. Moreover, the biosensor was applied to detect DA and UA in real biological serum samples using the standard addition method with satisfactory results.

Partially stabilised zirconia has advantages for the applications in the metallurgical processes which have special requirements in corrosion resistance and high-temperature performance. In the present work, controllable microwave heating was used for the uniform thermal field and consequent microstructure improvement to further improve the stability of partially stabilised zirconia, which was 88.14% prepared by electric arc melting. Analyses including X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy (Raman) were used to study the effect of temperature change on the phase composition and structure of the samples. After heating at temperatures of 900 °C, 1000 °C, 1100 °C, 1200 °C and 1300 °C for 1h, the stabilities of the heated product were 88.51%, 95.02%, 95.17%, 96.31% and 97.64%, respectively. From the phase transformations based on the experimental results, the discussion indicates that the martensitic transformation temperature of zirconia from m-ZrO2 to t-ZrO2 during the heating stage was reduced under the radiation of microwave energy.

In this work, microwave heating approach was introduced into the preparation process of zirconia materials to overcome the tricky technical defects during the traditional electric arc furnace method. Magnesia-partially stabilised zirconia (MgO-PSZ) with enhanced stability and a uniform microstructure was prepared via microwave heating of a ZrO2 sample manufactured by the electric arc furnace method. The effects of microwave heating on the phase stability properties, microstructure, and surface morphology of the prepared MgO-PSZ sample were evaluated via X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, and Scanning electron microscopy, and the obtained results suggested that the stability rate of the MgO-PSZ sample improved from the initial value of 81.19%–94.82% after microwave heating at 1300 °C for 1 h. As a result of the martensitic conversion of ZrO2 material, the m-ZrO2 diffraction peaks were suppressed at the same time. Additionally, a similar changing trend was noticed in the XRD pattern, Raman spectrum, and FT-IR spectrum, indicating a decrease in the m-ZrO2 phase content in the microwave treated products. Furthermore, the microstructure on the surface of the microwave-sintered MgO-PSZ sample was improved in contrast to the raw MgO-PSZ sample, and became relatively more uniform and smooth. This study determined the optimal microwave heating conditions for the preparation of MgO-PSZ material with enhanced performance, and can provided as a good foundation for developing the further related research on zirconia materials preparing by microwave heating technology.

Partially stabilized zirconia (PSZ) ceramics play a significant role as fundamental ceramics and refractory materials. In this work, a CaO-PSZ ceramics material was synthesized from fused ZrO2 by microwave sintering. The stability properties and structural characteristics of the products were characterized via X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results indicated that in a microwave field, the duration and sintering temperature presented similar influence trends for the stability properties of ZrO2 ceramics materials, which the finding was assigned to the phase transformation of ZrO2 with temperature change. In addition, following the microwave treatment of the fused zirconia sample at 1450 °C for 2.0 h, a cubic and monoclinic mixed phase was formed. These outcomes corresponded to the results from the SEM and energy dispersive X-ray (EDAX) analysis, demonstrating the successful preparation of the CaO-PSZ ceramics. The toughness of the ceramics was improved, which could be attributed to the formation of CaO-stabilizer-precipitated acicular crystals. The theoretical fundamentals and the practical cases presented in this paper are beneficial for the application of the microwave sintering technology in the synthesis of CaO-PSZ ceramics.

Applying microwave heating, in substitution for conventional industrial process heating, renders energy-saving and clean efficient for mineral reduction. In this work, the behavior of low-grade pyrolusite during microwave-assisted heating was systematically investigated, and the phase transformation of pyrolusite during the reduction process was characterized by TG-DTG-DSC and XRD; meanwhile, a model for the reduction mechanism was proposed, with a three-stage reduction process identified. Results indicated that manganese oxide (MnO) powder can be efficiently prepared, and the reduction ratio presented positive relationships with reduction temperature and heating time, obtaining with a high reduction ratio value of 94.4% achieved at 600 °C within a duration time of 40 min. XRD analysis confirmed that the phase transformation during the reduction process followed the conversion sequence as MnO2→Mn2O3→Mn3O4→MnO, and the iron oxides was almost converted to Fe3O4. It was proved that low-grade pyrolusite can be reduced effectively and efficiently to manganese oxide at lower temperature and shorter duration time by microwave heating.

Partially stabilised zirconia (PSZ) ceramics have attracted much interest because of their outstanding properties. In this study, fused ZrO2 was treated as a raw resource for the synthesis of CaO-PSZ ceramic materials through a facile sintering process. The crystal structure and thermomechanical properties of the synthesised CaO-PSZ ceramic samples were determined using XRD and SEM. The results revealed that various process parameters had different effects on the zirconia stability rate, including the temperature changing rate during the heating and cooling stages and the temperature and isothermal time during the quenching treatment; this was primarily a result of the thermodynamic characteristics of the martensitic conversion of ZrO2 ceramics. Secondly, the martensitic conversion process was revealed by XRD patterns, expressed as the partial conversion of c-ZrO2 to m-ZrO2. Meanwhile, SEM-EDAX analysis highlighted the precipitation behaviour of the CaO stabiliser and the successful preparation of CaO-PSZ ceramics by sintering, represented by the gathering phenomenon of the acicular grains and particles, as the findings matched the stability rate analysis. This study can supply a sound reference for the synthesis of CaO-PSZ ceramics from fused ZrO2.

Because of the shortage of natural rutile, synthetic rutile is a widely used substitute welding materials for natural rutile owing to its excellent mechanical and thermal properties. In this work, rutile TiO2 was prepared from oxidation roasting titanium slag, which can be used as special welding materials. The phase microstructure characteristics of the raw materials and the roasted samples were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier-transform infrared (FT-IR) spectroscopic analysis. Results indicated that the contents of sulfur (S) and carbon (C) in titanium slag decreased during oxidation roasting process, and the decreases of sulfur and carbon contents were mainly ascribed to the formation of corresponding oxides. XRD and FT-IR results revealed the formation of rutile TiO2 phase after titanium slag through oxidization roasting; additionally, observed from SEM patterns, the rutile TiO2 phase with a complex short rod-like crystal appeared in the products. Since the contents of sulfur (S), phosphorus (P) and carbon (C) element were all below 0.030% in the prepared rutile TiO2 with the recommended roasting approach (roasted at 1100 °C for 120 min), the present work highlights that Panzhihua titanium slag is a potential resource of titanium for the manufacture of high-quality rutile TiO2 applicable for special welding materials industry.

Hole-transporting materials (HTMs) capable of forming thermally stable amorphous film and possessing high electrochemical stability play an important role in organic light-emitting diodes (OLEDs), which can enhance the device performance. Herein, spirobifluorene-based HTM N-([1,1′-biphenyl]-2-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9,9′-spirobifluoren-2-amine (SFAF), employing fluorene-contained arylamine as the hole transporting unit, was synthesized, and the comprehensive properties of material were systematically investigated. Owing to the highly twisted spiro conformation, the SFAF exhibited a high glass transition temperature of 140 °C and a high thermal decomposition temperature of 402 °C. Moreover, a stably and homogeneously amorphous SFAF film was formed by increasing the treatment temperature up to 140 °C for 12 h and a smooth surface film was characterized by the atomic force microscope. In addition, the compound presented excellent electrochemical stability with nearly identical cyclic voltammetry curves during the 100 cycles. Green fluorescent OLED based on SFAF as the hole-transporting layer showed a satisfactory device performance. The SFAF with high stability was also applied as HTM in phosphorescence device, which exhibited a turn-on voltage of 2.2 V, a maximum brightness of 191127 cd m−2 and the maximum current efficiency of 63.80 cd A−1. This results indicate that SFAF is a great promising and potential hole-transporting material for highly efficient optoelectronic devices.

Given the complexity of injurious ingredients in practical wastewater, development of effective and low-cost multifunctional materials to decontaminate wastewater is of great necessity. Herein, polyacrylonitrile (PAN)/AgBr/Ag fibrous membranes are rationally designed and fabricated using combined electrospinning and wet-chemical methods. The surface AgBr/Ag Schottky junction is simply generated on hydrophilic PAN fibers by epitaxial growth approach, which simultaneously reveals superior photodegradation performance towards a variety of mimetic organic pollutions and excellent antibacterial activity due to their electron synergetic effect. Moreover, the stable porous structure of PAN/AgBr/Ag membranes and its good mechanic strength also ensures its good filtration performance. Overall, the PAN/AgBr/Ag fibrous membrane reveals water purification ability towards the simulated wastewater. In addition, benefit from the low content of Ag in PAN/AgBr/Ag membrane and easily scale-up, the self-standing PAN/AgBr/Ag membrane reveals great potential to practical wastewater treatment.

Rational design and preparation of electrocatalyst with optimal component and interfaces, which can work well for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline media, are of great importance in practical water splitting. Herein, a multiscale structure surface engineering approach to construct Co(OH)2/Ag/FeP hybrid as efficient electrocatalysis for water splitting in alkaline media is reported. By optimizing the component ratio and engineering interfacial structure, the Co(OH)2/Ag/FeP hybrid eletrocatalyst exhibits promoted HER and OER activity as well as stability in alkaline media, achieving an overpotential of 118 and 236 mV at a current density of 10 mA cm–2, respectively. Further experimental characterizations demonstrate the electron structure changes in Co(OH)2/Ag/FeP hybrid after constructing the interfaces, which is beneficial to generate low-charge state Fe2+ and high-oxidized Co3+/4+. The first-principle calculations reveal that the dissociation of H2O at...

Utilizing surface polarization to improve the separation efficiency of photoinduced carriers is considered to be an effective strategy to enhance the photocatalytic activity. Herein, a novel nonprecious metal-based P-doped g-C3N4 (PCN)/polyaniline (PANI)/BaTiO3 (BTO) (PPB) ternary photocatalyst with a hollow architecture was rationally designed and prepared by a combined wet-chemical and thermal treatment strategy. Except for the Z-scheme involved in PCN and PANI, the vertical polarization provided by ferroelectric BTO further improved the separation efficiency of the photoinduced charge carrier, resulting in an enhanced visible-light photocatalytic hydrogen production activity of 602 μmol h−1 g−1, which was 21-fold higher than that of pristine g-C3N4, and an apparent quantum efficiency of 4.16% at 420 nm. In addition, benefitting from this ternary heterojunction, the photoinduced electrons were concentrated on the intermediate p-type PANI while holes were left on the lateral n-type PCN involved in the Z-scheme, resulting in the retention of high oxidation–reduction potentials. Moreover, this approach to enhance the photocatalytic activity by constructing a Z-scheme heterojunction and surface polarization could expand to other photosystems, which provides a new avenue for the rational design and the synthesis of novel photocatalysts.

Bornyl caffeate was initially discovered as a bioactive compound in medicinal plants. Despite the promising pharmacological activities including anti-tumor and antibacterial activities, the pharmacokinetics of the compound remain open. This work developed a high performance liquid chromatography-tandem mass spectrometric method for the determination of bornyl caffeate and caffeic acid (major metabolite and a main unit of bornyl caffeate) in vivo. Successful application of the method included identification of its metabolites and investigation on the drug pharmacokinetics. A total of 30 compounds were identified as the metabolites of bornyl caffeate in rats. We attributed these metabolites to phase I metabolic routes of reduction, oxidation, hydrolysis and phase II metabolic reactions of glucuronidation, sulfation, O-methylation and glycine. Glucuronidation, sulfation, O-methylation and reduction were the main metabolic pathways of bornyl caffeate. The method presented a linear range of 1–4000 ng mL−1. The pharmacokinetic profile of bornyl caffeate was found to be a three compartment open model, while caffeic acid fitted to a two compartment open model when it was administered alone or served as the main metabolite of bornyl caffeate. The time to peak concentration (Tmax) and the maximum plasma concentration (Cmax) of bornyl caffeate were 0.53 h and 409.33 ng mL−1. Compared with original caffeic acid, the compound displayed an increased half-life of elimination (T1/2β), area under the concentration time curve from 0 to t (AUC0–t) and area under the concentration time curve from 0 to ∞ (AUC0–∞), a decreased half-life of absorption (T1/2α) and an identical Cmax. Taking together, we concluded that bornyl caffeate is able to rapidly initiate therapeutic effect and last for a relatively long time in rats; metabolic pathways of O-methylation and reduction is key to interpret the mechanism and toxicity of bornyl caffeate.

Phenology is an indicator of crop growth conditions, and is correlated with crop yields. In this study, a phenological approach based on a remote sensing vegetation index was explored to predict the yield in 314 counties within the US Corn Belt, divided into semi-arid and non-semi-arid regions. The Moderate Resolution Imaging Spectroradiometer (MODIS) data product MOD09Q1 was used to calculate the normalized difference vegetation index (NDVI) time series. According to the NDVI time series, we divided the corn growing season into four growth phases, calculated phenological information metrics (duration and rate) for each growth phase, and obtained the maximum correlation NDVI (Max-R2). Duration and rate represent crop growth days and rate, respectively. Max-R2 is the NDVI value with the most significant correlation with corn yield in the NDVI time series. We built three groups of yield regression models, including univariate models using phenological metrics and Max-R2, and multivariate models using phenological metrics, and multivariate models using phenological metrics combined with Max-R2 in the whole, semi-arid, and non-semi-arid regions, respectively, and compared the performance of these models. The results show that most phenological metrics had a statistically significant (p &lt, 0.05) relationship with corn yield (maximum R2 = 0.44). Models established with phenological metrics realized yield prediction before harvest in the three regions with R2 = 0.64, 0.67, and 0.72. Compared with the univariate Max-R2 models, the accuracy of models built with Max-R2 and phenology metrics improved. Thus, the phenology metrics obtained from MODIS-NDVI accurately reflect the corn characteristics and can be used for large-scale yield prediction. Overall, this study showed that phenology metrics derived from remote sensing vegetation indexes could be used as crop yield prediction variables and provide a reference for data organization and yield prediction with physical crop significance.

With the growing concern about safety and environmental issues, amino acid-based surfactants have great potential as sustainable and eco-friendly substances. In the present study, six N-acyl oligopeptide surfactants were synthesized using fatty acid methyl esters (i.e., methyl caprate, methyl laurate, and methyl myristate) and glycyl oligopeptides (i.e., glycylglycine and glycylglycylglycine). Surface active properties and aggregation behaviors of these surfactants were investigated using surface tension, fluorescence probe, dynamic light scattering, and microscopy measurements. The adsorption at the air-water interface and aggregation in the aqueous solution depend on the structure of both hydrophilic head-groups and hydrophobic tails. Spherical vesicles were observed in the aqueous solutions of glycylglycine derivatives, whereas short tubular aggregates were found in that of corresponding glycylglycylglycine products. Intermolecular hydrogen-bonding interaction between the amide head-groups might be responsible for the different self-assembly behavior and microstructure of N-acyl oligopeptide surfactants in the aqueous solution.

Using the vibrating sample magnetometer and ex situ vector network analyzer ferromagnetic resonance, the static and dynamic magnetic properties of Tb (4 nm)/Cr ( t Cr )/Ni 80 Fe 20 (12 nm) trilayers with different thickness of Cr layer (from 0.2 to 4.0 nm) were investigated comparing with those of Ni 80 Fe 20 film. From the results of in-plane static magnetic hysteresis loops, we analyzed the soft magnetic properties and in-plane anisotropy, along with obtaining the saturation magnetization ( M s ) which shows no obvious reducing and a modulation akin to RKKY coupling. By fitting the relationship of resonance field and linewidth versus resonance frequency, the effective magnetization 4π M eff , gyromagnetic ratio γ , and effective damping coefficient ( α eff ) were extracted. It is worthwhile to mention that the inserting of ultrathin Cr layer (0.2 nm) enhanced the above parameters obviously, which then backed down towards their values in Ni 80 Fe 20 film with increasing the thickness of Cr layer as a result of the weakening magnetic proximity effect and the decreasing spin-pumping effect in trilayers. Finally, they became flattening with the Cr layer thicker than 1 nm where oscillations are also observed in the value of γ and α eff. Interestingly, the oscillations in α eff and γ are consistent with each other, which implies the damping mechanism mainly related to the spin-orbit coupling originating from the indirect interaction between Tb and Ni 80 Fe 20 . In addition, the inhomogeneous broadening (Δ H 0 ) were determined to be very small which further ascertain the accurate of the α eff .

As a representative formulation of Radix Salviae miltiorrhizae (Danshen)-Lignum Dalbergiae odoriferae (Jiangxiang), Xiangdan injection is widely prescribed for cardio- and cerebrovascular diseases in practice. This necessitates a pharmacokinetic investigation of this formulation to make it safer and more broadly applicable. We developed and validated a sensitive, selective, and reliable high-performance liquid chromatography with tandem mass spectrometry method for the simultaneous determination of 11 phenolic compounds including danshensu plus two diterpenoid quinones like cryptotanshinone and tanshinone IIA in rat. We applied this method for the pharmacokinetic studies of the 13 compounds in a rat model of middle cerebral artery occlusion after intravenous injection of Xiangdan injection or Danshen injection. In sham-operated rats, the animals taking Xiangdan injection exhibited significant growth of the area under the curve for danshensu, protocatechuic aldehyde, and tanshinone IIA compared with the changes seen in the data of those administrated with Danshen injection. Such a pattern was also observed in middle cerebral artery occlusion rats, whereas increased the area under the curve values were observed for danshensu, protocatechuic aldehyde, caffeic acid, rosmarinic acid, and tanshinone IIA. These results demonstrated that synergistic interactions occurred between the components of Danshen and the active compounds of Jiangxiang both in sham-operated and middle cerebral artery occlusion rats, increasing the bioavailability of Danshen. The results presented herein can be used to determine a reference dose for the clinical application of Xiangdan injection, and to elucidate the synergistic mechanism of Danshen and Jiangxiang.

Bifunctional rambutan-like nanosphere has been synthesised by combining the Au nanoparticles and polyluminol encapsulating with glucose oxidase using the one-pot hydrothermal redox protocol for the first time. Au nanoparticle/polyluminol/glucose oxidase (Au/PLUM/GOD) was developed via one step reaction through luminol solution redox reacted with HAuCl4 aqueous solution containing glucose oxidase protected from light at room temperature for 48 h. Highly luminescent luminol serves as a luminescent marker, while GOD possess high enzyme-catalytical charateristics when encapsulated in the bifunctional nanospheres. The synthetic method is easy, environmental friendly and high-productive. The prepared nanocomposites were used simply and effectively to develop highly sensitive solid-state electrochemiluminescent sensor for determination of glucose in human serum samples with wide linear range. Furthermore, it provided a promising approach for various biomolecule ECL sensors characterized by the parallel operative effects of both enzymic activities and the available concentrated surface luminescent molecules.

A highly binding dummy template molecularly imprinted polymers (Fe3O4-NH2@GO@MIPs) was synthesized used Fe3O4-NH2@GO as carrier by dummy surface molecular imprinting technique (DSMIT) for the first time. Fe3O4-NH2@GO@MIPs were characterized by fourier transform infrared (FT-IR), scanning electron microscope (SEM), transmission electron microscope (TEM), thermogravimetric analysis (TGA), brunauer emmett teller (BET) and vibrating specimen magnetometer (VSM). Adsorption and selectivity experiments of Fe3O4-NH2@GO@MIPs and non-imprinted polymers (Fe3O4-NH2@GO@NIPs) verified that the Fe3O4-NH2@GO@MIPs had a better selectivity and adsorption properties for five pyrethroids pesticides. Adsorption test results revealed that the adsorption behaviors of pyrethroids onto Fe3O4-NH2@GO@MIPs followed Langmuir equation adsorption isotherm and pseudo-second-order kinetic models. Fe3O4-NH2@GO@MIPs were used as sorbent in magnetic solid phase extraction (MSPE) to extract five pyrethroids from fruit juice samples, following desorption with acidified ethyl acetate, the pyrethroids were quantified by gas chromatography with electron capture detection (GC-ECD). The developed method MSPE coupled with GC-ECD achieved satisfactory recovery (72.1–106.8%) with RSD less than 10.8%, and the detection limits (LOD) for fenpropathrin (FENP), lambda-cyhalothrin (LC), cyfluthrin (CYF), fenvalerate (FEN) and deltamethrin (DEL) ranged from 0.007 to 0.015 μg/L. Compared to other methods, the procedure MSPE-GC-ECD based on Fe3O4-NH2@GO@MIPs in this work demonstrated to be a more convenient and practical method for the separation, enrichment, and detection of pyrethroids pesticides from fruit juice samples.

Tanshinol borneol ester (DBZ) is a potential drug candidate composed of danshensu and borneol. It shows anti-ischemic and anti-atherosclerosis activity. However, little is known about its metabolism in vivo. This research aimed to elucidate the metabolic profile of DBZ through analyzing its metabolites using high-performance liquid chromatography combined with electrospray ionization quadrupole time-of-flight mass spectrometry. Chromatographic separation was performed on an Agilent TC-C18 column (150 × 4.6 mm, 5.0 μm) with gradient elution using methanol and water containing 0.2% (v/v) formic acid as the mobile phase. Metabolite identification involved analyzing the retention behaviors, changes in molecular weights and MS/MS fragment patterns of DBZ and its metabolites. As a result, 20 potential metabolites were detected and tentatively identified in rat plasma, urine and feces after administration of DBZ. DBZ could be metabolized to O-methylated DBZ, DBZ-O-glucuronide, O-methylated DBZ-O-glucuronide, hydroxylated DBZ and danshensu. Danshensu, a hydrolysis product of DBZ, could further be transformed into 12 metabolites. The proposed method was confirmed to be a reliable and sensitive alternative for characterizing metabolic pathways of DBZ and providing valuable information on its druggability.

Uncovering community structures is a fundamental and important problem in analyzing the complex networks. While most of the methods focus on identifying node communities, recent works show the intuitions and advantages of detecting link communities in networks. In this paper, we propose a non-negative matrix factorization (NMF) based method to detect the link community structures. Traditional NMF-based methods mainly consider the adjacency matrix as the representation of network topology, while the adjacency matrix only shows the relationship between immediate neighbor nodes, which does not take the relationship between non-neighbor nodes into consideration. This may greatly reduce the information contained in the network topology, and thus leads to unsatisfactory results. Here, we address this by introducing multi-step similarities using the graph random walk approach so that the similarities between non-neighbor nodes can be captured. Meanwhile, in order to reduce impact caused by self-similarities (similarities between nodes themselves) and increase importance gained from similarities between other different nodes, we add a penalty term to our objective function. Then an efficient optimization scheme for the objective function is derived. Finally, we test the proposed method on both synthetic and real networks. Experimental results demonstrate the effectiveness of the proposed approach.