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Future artificial intelligence circuits will require expandable electronic synapses with extremely high bit density and computing speed. In this regard, the nanostructure of two-dimensional materials achieves the goal and provides device scalability in both horizontal and vertical dimensions. In this work, we report the nonvolatile bipolar resistive switching characteristics of Ni–Al layer double hydroxide (LDH)-adsorbed thiadiazole memristors. The Ni–Al LDH-adsorbed thiadiazole memristors implement a progressive reduction process and can be used to simulate the “learning” and “forgetting” functions of biological synapses. At the same positive and negative voltage pulse width, multiple resistance stages can be observed for continuous pulse number. In addition, the application of pulse train operation scheme is an effective method to control the simulated synaptic devices during the reset process, which helps understand the nature of the evolution of conductive nanofilaments.

To evaluate the synergetic adsorption capacity of layered double hydroxide (LDH) and photocatalytic reduction property of TiO2 for aqueous Cr(VI), the Fe3O4-ZnAl-LDH and TiO2 composites (FLT) were prepared via sol-gel method. The removal efficiency of FLT composites for Cr(VI) changed with the mass ratio of Fe3O4-LDH/TiO2, and the optimal ratio was 20% (FLT-2). The adsorption efficiencies of 100 mg FLT-2 were 74% and 64% for 20 and 50 mg/L Cr(VI) solution, and the total removal ratios of Cr(VI) were all over 97% after UV irradiation. The experimental data of adsorption kinetic, adsorption isothermal, and photocatalytic reduction were consistent with the pseudo-second-order, Langmuir, and first-order reaction equations, respectively. From the X–ray photoelectron spectra analysis, FLT composites adsorbed Cr(VI) directly via surface complexation, also reduced aqueous Cr(VI) to Cr(III). The photocurrent and electrochemical impedance spectroscopy of FLT composites indicated the photo-induced electron-hole pairs were separated effectively. The regeneration results show that the FLT composites had good stability and reusability after five consecutive cycles. Therefore, FLT composites are promising materials in the disposal of wastewater containing Cr(VI).

Mesoporous CoFe2O4 nanowires (NWs) were prepared with ordered mesoporous SBA-15 silica, and then were used to activate peroxymonosulfate (PMS) to degrade ciprofloxacin (CIP). All results showed that mesoporous CoFe2O4 NWs efficiently activated PMS and greatly improved the degradation of CIP in aqueous solution. The influence of PMS and CoFe2O4 on the CIP removal was taken into accounted, which indicated that the dominant sulfate radicals for the CIP degradation. Mesoporous-structure of CoFe2O4 NWs could absorb CIP and PMS in high concentration near CoFe2O4 NWs and promoted this degradation. The 100 ml CIP (20 mg/L) could be completely removal in the optimum conditions with 2 mM PMS and 0.3 g/L S-130, and the CIP removal presented the excellent recyclability with the CIP degradation as high as about 93% after four consecutive cycles. Owing to the high efficiency, excellent magnetic respond and good reusability, mesoporous-structured CoFe2O4 NWs could be regarded as the promising heterogeneous catalysts for PMS to degrade CIP.

Here we demonstrate high-performance ethanol sensors based on Fe-doped In2O3 mesoporous nanospheres. By using FDU-12 as template via a facile one-step impregnation method Fe-doped In2O3 were synthesized, which display high surface area, uniform shape, ordered mesoporous structure and small particle size. The Fe-doped In2O3 exhibited a larger response to ethanol gases than pure In2O3 under all measured concentrations. Furthermore, the effect of Fe/In molecular ratio on sensing property was investigated by comparing their response. The enhanced sensing properties could result from the unique mesoporous structure and the synergic electronic interaction between the guest Fe dopant and the host In2O3 material.

One-dimensional nickel (Ni) microwires were synthesized by the magnetic-field-induced (MFI) microemulsion-hydrothermal method using Ni nanospheres as seeds. The influence of the chemical conditions and magnetic field on the morphology and magnetic properties of Ni microwires were investigated by X-Ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometry (VSM). The strength of magnetic field greatly affected the morphology and magnetic properties of Ni microwires. The growth and morphology of Ni microwires depended on the competition between Brownian motion and magnetic dipole moments from magnetic field. The larger nanoparticles with the higher magnetic moments preferred to form one-dimensional Ni microwires and their length increased up to several millimeters with the increasing magnetic field strength, while the average diameter of Ni microwires decreased. Furthermore, the easy magnetization direction of Ni microwires was parallel to the direction of magnetic field and the Ni microwires axis.

To understand the possible mechanisms of hexavalent chromium (Cr(VI)) adsorption on the surface of modified layered double hydroxides (LDHs), we synthesized ethylenediaminetetraacetic acid intercalated MgAl-LDH (LDH-EDTA) and its magnetic product (Mag-LDH-EDTA), and evaluated their adsorption performance for Cr(VI) by batch equilibrium experiments. The characterization analysis proved that the EDTA was intercalated into MgAl-LDH and the adsorbents had an ordered structure and abundant functional groups. The adsorption mechanisms of Cr(VI) by LDH-EDTA and Mag-LDH-EDTA could be attributed as electrostatic attraction, surface complexation, anion exchange, and reduction reaction speculating from the detailed X-ray diffraction patterns (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and zeta potential analysis. The removal ratio remained above 96% and 79% for 50 mg L−1 Cr(VI) using 0.03 g LDH-EDTA and Mag-LDH-EDTA, respectively. The adsorption process was less influenced by the pH value of the aqueous solution. The pseudo-second-order model and the Langmuir equation well fitted to the adsorption kinetic and isotherm data. Thus, the EDTA intercalated LDH materials had potential applications for Cr(VI) removal in real wastewater treatment.

Black carbons (BCs) are ubiquitous in the natural environment and can significantly influence the environmental behavior of pollutants. This work examined the mediating effects of graphite, soot, and biochar on 1-naphthylamine (1-NA) oxidation under aerobic conditions. It was shown that the three BCs significantly promoted the oxidation of 1-NA in the dark, and the mediation efficiency of graphite was much greater than that of soot or biochar. The oxidation products were the coupling oligomers (dimers and trimers) and the oxygen-containing oligomers of 1-NA (di-OH-1-NA, OH-azo naphthalene, OH-trimers and amino-naphthoquinone derivatives etc.). The phenolic OH on BCs were identified as the active sites for 1-NA oxidation, which could stimulate O2 to produce reactive oxygen species through successive single electron transfer and then cause 1-NA oxidation. Moreover, the superior catalytic performance of graphite was also related to its high electrical conductivity. The synergies between the sp2-hybridized carbon surface and the active sites (such as phenolic OH and defects) facilitated the oxidation of 1-NA on graphite. Findings in this study not only are helpful for better understanding the reactivity of environmental BCs, but also provide new insights into the risk assessment of 1-NA in the natural environment.

Mesoporous indium (In)-doped hematite (α-Fe 2 O 3 ) nanowires were synthesized with mesoporous SBA-15 silica as a hard template, and then the influence of In dopant on the microstructure and gas-sensing performance was investigated in detail. With characterization by transmission electron microscopy, X-ray diffraction, UV–vis spectroscopy, and nitrogen physisorption experiments, it was shown that the average grain size increased for up to 1 mol% In dopant and then decreased with increasing In dopant content, while the surface area changed in the inverse manner. Because of the low melting point of In, In acted as a fluxing agent and entered the α-Fe 2 O 3 lattice when the In content was low, and the average grain size increased. With higher In content, In precipitated out the lattice and existed at the grain boundary, and the grain size decreased. It is concluded that In in the lattice increased lattice distortion and In at the boundary increased the surface area and oxygen vacancies, which were both beneficial for improving the gas-sensing performance. The response of In-doped α-Fe 2 O 3 nanowires increased by about 30%–50% as compared with that of pure α-Fe 2 O 3 nanowires. The gas sensor based on 3 mol% In–doped α-Fe 2 O 3 nanowires exhibited the best gas response and a rapid response-recovery time toward ethanol at the optimum temperature. Owing to the same valence, In dopant affected only the microstructure and components of the α-Fe 2 O 3 lattice, which was necessary to improve the gas-sensing behavior.

A uniform magnetic field was applied to prepare Ni-epoxy resin functionally graded material (FGM) with gradient and anisotropy both in microstructures and resulting properties. By moving a magnetic field imposed on the green sample perpendicular to the field direction from one end to the other, Ni particles were driven by the field and distributed gradually in epoxy resin matrix. The gradient of light transmittance and electrical resistivity reflected the graded structures in Ni-epoxy resin composite. Furthermore, Ni particles aggregated to form chain clusters along the field direction, which produced anisotropic electrical properties in direction along and perpendicular to the chains. It has been clearly proved that the magnetic-field-driving method is a facile and effective attempt to prepare FGMs.

Mesoporous Co3O4 nanowires were synthesized with the nanocasting method, and then the dispersed Co 3O4 nanowires (Co3O4-DNWs) were separated from the bundled Co3O4 nanowires (Co3O4-BNWs) by the centrifugation technique. From the characterization with TEM, X-ray diffraction, UV–vis spectra and nitrogen adsorption-desorption isotherm, both samples present the same mesoporous-structure, diameter and the similar defects due to the same synthesis conditions. All results indicate that the microstructures and morphology of Co3O4 nanowires greatly affect the toluene gas sensing performance. Owing to the mesoporous-structures with the high surface area, the sensitivities of both samples are higher than others’. Co3O4-DNWs exhibit the higher specific surface area (44.98 m2 g−1) than Co3O4-BNWs, leading to the excellent gas-sensing properties to toluene gas at the optimized operating temperature of 210℃. Moreover, both samples present the excellent stability and selectivity to toluene gas. The gas-sensing mechanism results from the surface oxygen and toluene gas adsorption through comparing the sensitivity of Co3O4-DNWs and Co3O4-BNWs.

Magnetic NiFe 2 O 4 /SBA-15 nanocomposites were synthesized by a facile impregnation method, and NiFe 2 O 4 nanoparticles presented spinel phase structure and existed in the mesopores of SBA-15. Partial mesopores were blocked by NiFe 2 O 4 nanoparticles and micropores formed, which the capillarity of micropores played a decisive role for methylene blue (MB) adsorption. The saturation magnetization increased from 2.34 emu g −1 to 10.03 emu g −1 with the NiFe 2 O 4 content, while the specific surface area decreased from 552.18 m 2 g −1 to 260.40 m 2 g −1 and pore volume decreased from 1.13 cm 3 g −1 to 0.49 cm 3 g −1 . MB adsorption could be improved by optimizing the NiFe 2 O 4 content of the nanocomposites. MB could be adsorbed completely in 60 min with the optimum nanocomposites and could be separated easily from water by magnetic separation technique.

In this paper, the mesoporous NiO nanowires (NWs) were synthesized by using SBA-15 silica as the hard templates with the nanocasting method, and then calcined from 550 to 750 °C. X-ray diffraction, transmission electron microscopy (TEM), nitrogen adsorption/desorption isotherm and UV-vis spectrum were used to characterize the morphology, phase structure and microstructure of the as-prepared samples. All results indicated that the calcination temperature greatly affected crystallization degree and specific surface area of the as-prepared NiO NWs. And the crystallization degree increased and specific surface area decreased with the calcination temperature. The higher specific surface area created more active sites for the surface redox reaction, while the higher crystallization degree led to the wider bandgap and made the charge carriers transport easily. It was concluded that the calcination temperature of NiO NWs greatly affected the gas-sensing performance. The optimized results from the gas-sensing behavior indicated that NiO NWs-650 based sensor exhibited the highest sensitivity to ethanol for the suitable calcination temperature. Furthermore, NiO NWs-650 sensor exhibited a better selectivity to ethanol than n-hexane, methanol, acetone and formaldehyde.

Nickel oxides (NiO) nanowires were synthesized using the ordered mesoporous silica SBA-15 as hard templates with the nanocasting method, and then mesoporous NiO nanowires (NiO MNWs) were separated from the dispersed NiO nanowires (NiO DNWs) by the centrifugation technique. XRD, TEM, nitrogen adsorption/desorption isotherm and UV–vis spectrum were used to characterize the phase structure and microstructure. Both samples existed in bundles with the different grain size and NiO MNWs with the larger grain size presented the higher mesopores percent. The specific surface area (92.61 m 2 /g) and bandgap (3.31 eV) of NiO MNWs were higher than those of NiO DNWs for the higher mesoporous-structure. Therefore, the NiO MNWs based sensor exhibited the good sensitivity and fast response-recovery to ethanol at 340 °C. The gas-sensing properties of NiO MNWs were better than those of the NiO DNWs, which should be attributed to the higher surface area and wider bandgap.

Hydrogen peroxide (H 2 O 2 ) is a key molecule in biology. As a byproduct of many enzymatic reactions, H 2 O 2 is also a popular biosensor target. We report the first use of uniform nanoparticles of porphyrin functionalized ceria (Por-Ceria) prepared by a one-step method, as a colorimetric probe in detection for H 2 O 2 . Por-ceria nanoparticles exhibited strong intrinsic peroxidase activity toward a classical peroxidase substrate, 3,3′,5,5′-tetramethylbenzidine (TMB), in the presence of H 2 O 2 . Enhanced peroxidase-like activity of Por-ceria originated from synergistic effect of porphyrin and ceria, thereby explaining the high performance of Por-Ceria as an artificial enzyme mimicking peroxidase. When coupled with glucose oxidase, glucose is detected. A detection limit of 1.9 × 10 −2 mM glucose with a linear range up to 0.15 mM.

In this paper, MnZn ferrites were used as coating agents to prepare MnZn/FeSiAl soft magnetic composites (SMCs) in order to improve the magnetic property, because of the higher permeability of magnetic MnZn ferrites than that of traditional coatings which are always nonmagnetic. The effects of molding pressure, annealing temperature, and content of insulation on the soft magnetic properties of MnZn/FeSiAl SMCs were studied. With increasing molding pressure, the effective permeability of the SMCs increased firstly and then decreased, while the core loss decreased firstly and then increased, and both have the best performance at 1.6 GPa. The permeability increased with increasing temperature, reached the maximum value at 660 °C and then decreased, while the core loss decreased with increasing temperature to 700 °C and then increased. The permeability increased with increasing MnZn content from 0.1 to 3% and then decreased, while the D-C bias property continuously increased.

Plate-like hexagonal SrFe12O19 particles were synthesized by hydrothermal process. The as-synthesized particles were dispersed evenly in epoxy resin and then took root in the curing epoxy matrix under a uniform magnetic field. The microstructures, morphologies, magnetic and electromagnetic properties of the composites were studied. The plate-like particles were arranged with the plates perpendicular to the field direction. This demonstrated that the easy axis of the particle was perpendicular to the plate. There were obvious differences in remanent magnetization (Mr) among the aligned sample with the plates parallel to the testing direction (parallel sample), the aligned one with the plates perpendicular to the testing direction (perpendicular sample), and the nonaligned one (nonaligned sample). The perpendicular sample was better at storage capacity of electric and magnetic energy than the others. This indicated both the polarization and domain wall displacement were different between the easy axis direction and the hard axis one. The parallel sample caused maximum dielectric loss and the perpendicular sample caused minimum dielectric loss in the frequency range 2–12 GHz and 14.4–18 GHz, while it was reverse in the frequency range 12–14.4 GHz. The nonaligned sample caused maximum magnetic loss in the low frequency range, while the aligned samples were not superior at magnetic loss in the whole frequency range.

Nyssa yunnanensis is a critically endangered species endemic to China. Here, we assembled and characterized the plastome of N. yunnanensis using Illumina paired-end data. The assembled plastome is 156,544 base pairs (bp) in length, containing a large single-copy (LSC) region of 86,056 bp, a small single-copy (SSC) region of 18,262 bp, and two inverted repeat (IR) regions of 26,113 bp. The plastome possesses total 125 genes, including 81 protein-coding genes, eight rRNA genes, and 36 tRNA genes. In addition, the overall GC-content of the whole plastome is 37.9%, while the corresponding values of the LSC, SSC, and IR regions are 36.0, 32.2, and 43.0%, respectively. Furthermore, phylogenetic analyses show that N. yunnanensis is closely related to the species of Camptotheca acuminata.

Mesoporous gas-sensitive nanomaterials have attracted the attention of more and more researchers because of their excellent stability and selectivity. Herein, pure and cerium-doped indium oxide 3D nanosphere (26–19 nm in diameter) arrays were synthesized via nanocasting using mesoporous silica as hard templates. The content of the Ce dopant ions has been found critical to control the structure, optical properties, and gas-sensing activities of the materials. The Ce-doped indium oxide shows significantly improved gas-sensing properties as compared to undoped indium oxide. And the sensor fabricated from the 3 mol% Ce-doped In2O3 with mesoporous nanospheres exhibited excellent sensing properties to ethanol at the optimum temperature of 330 °C. The significantly improved sensing performances may be ascribed to the mesostructured morphology and the doping of Ce ion. Optimizing the performance of mesoporous gas-sensing materials through various channels still requires our continuous efforts.

The Pt/NiCo layered double hydroxides nanocomposites (Pt/NiCo-LDH NCs) have been successfully prepared by a one-pot hydrothermal method. Pt/NiCo-LDH was demonstrated to possess an excellent peroxidase-like activity together with a weak oxidase-like activity, evaluating in virtue of rapid catalytic oxidization of 3, 3′, 5, 5′-tetramethylbenzidine (TMB) by H2O2 into a blue oxidation product (oxTMB) only in 30 s. The short response time is very important for designing colorimetric sensors to realize real time detection. The catalytic behaviors of Pt/NiCo-LDH followed the Michaelis-Menten kinetics, possessing a good affinity towards both TMB and H2O2. The catalytic mechanism of Pt/NiCo-LDH is due to OH radicals from decomposing of H2O2. Based on the high peroxidase mimetic activity of Pt/NiCo-LDH, a rapid and convenient colorimetric sensing platform for H2O2 and glutathione has been successfully constructed. Under optional conditions, the colorimetric platform shows a sensitive response to H2O2 and glutathione in the linear range of 10–90 mM and 50–500 mM with a limit of detection of 0.76 mM and 3.77 mM, respectively.

Platelet-like hexagonal SrFe 12 O 19 particles were prepared by hydrothermal synthesis, and the effects of molar ratio of Fe/Sr ( R Fe/Sr ) on the phase compositions, morphologies and magnetic properties of as-prepared samples were investigated. The optimum R Fe/Sr is identified as 8:1. The hexagonal platelet-like particles are nano-scale in thickness and micro-scale in diameter. The low coercivity is a consequence of the large shape anisotropy of the as-synthesized particles. The platelet-like hexagonal SrFe 12 O 19 particles were then dispersed in epoxy resin and formed ordered arrangement structure which took root in the curing epoxy matrix under an external magnetic field of 8000 Oe. The microstructures, morphologies and magnetic properties of the bulk samples orientated and nonaligned were studied. The platelet-like particles arrange with the platelet perpendicular to the magnetic field direction in the orientated samples. This demonstrates that the easy axis of the particle is perpendicular to the platelet, and that the magnetocrystalline anisotropy still plays a leading role in the changing effective anisotropy with the rapidly growing shape anisotropy. The remanence ( Mr ) of the bulk samples is changed obviously after orientation, while the coercivity nearly remains constant. That is, the maximum energy products ( BH ) max can be effectively adjusted by given a suitable magnetic field.

A series of Eu3+-activated Li2Mg2(WO4)3 (LMW) materials were synthesized by high temperature solid state reactions. The phosphor can be effectively excited by 394 nm near ultraviolet light and emit intense red light with high color purity. Prepared phosphors can be indexed to LMW with particular lyonsite structure. The occupation of Eu3+ in LMW is selective. Most of Eu3+ comes into 1A sites without inversion symmetry. The present research suggests that LMW is a suitable host for luminescence applications and Eu3+-activated LMW is a promising phosphor for phosphor-converted white light-emitting diodes.

Application of municipal sewage sludge to agricultural land especially in shallow soils, demands to validate the maximum amount of heavy metal, monitoring its effects on soil and on plants. The use of sewage sludge as a fertilizer and soil amendment has resulted in high concentrations of heavy metals in the soil and food limiting its use. Controlling the pollution of heavy metals is the key factor to realize the safe utilization of sewage sludge. In the present study, the heavy metal stabilizers were added to sludge contained in used plastic containers, through artificially watering or naturally rain falling, the nutrient components flowed out with leaching water and fertilized plants but the heavy metals retained in the sludge within container. The potential toxic risks from heavy metals of sludge depend on their chemical speciation. The contents of heavy metals in different treatments were analyzed and their speciation was determined. The pot experiments with plants (Zea mays and Laetuca satiuali) showed that the positive effects of the mixture of the sludge and K2SO4 on plant production and reduction of heavy metal contents in plants were significant. The BCR sequential extraction procedure was applied for measurement of heavy metals in the experimental sludge. The results showed that the concentrations of Zn were predominant in acid exchangeable and reducible fractions, and Cu was principally distributed in oxidizable fractions. Metals-bound sludge could be collected easily after treatment to prevent the secondary pollution, provided the heavy metals were fixed within the container and reduced obviously the leaching of heavy metals to soil.

Highly ordered La0.5Ca0.5MnO3 nanowires bundles are synthesized using mesoporous SBA-15 silica as the hard template. The magnetic properties and critical behaviors of the ferromagnetic–paramagnetic (FM–PM) phase transition of the La0.5Ca0.5MnO3 nanowires bundles are investigated through isothermal magnetization methods. The calculated results show that the FM–PM transition is second order and the magnetic interaction has some deviations from the mean-field model. Though the obtained critical parameters of β = 0.596 ± 0.009, γ = 1.131 ± 0.008 and δ = 2.99 ± 0.05 follow the Widom scaling relation δ = 1 + γ/β and the single scaling equation M(H,|e|) = eβf±(H/|e|β+γ), the critical exponents do not obey the magnetization entropy scaling theory, indicating that the nanometer-size effect play a significant role on the magnetic phase transition and magnetic entropy for La0.5Ca0.5MnO3 nanowires bundles.

Mesoporous n-type hematite bunched nanowires (α-Fe2O3 BNWs) and Zn-, In- and Sn-doped α-Fe2O3 BNWs were synthesized by nanocasting method, and then the influence of the different-valence metals-doping on the microstructures, components and gas-sensing properties is discussed in detail. All samples present mesoporous-structure and are composed of the uniform α-Fe2O3 nanowires. The Zn, Fe, Sn and In-doped concentration decreased with the increasing radius of their hydrated ions. The ethanol gas-sensing results indicate that the different-valence metals-doping greatly affects the response of α-Fe2O3 BNWs sensors to ethanol gas. The sensitivity to 100 ppm ethanol gas increased from 10.046 for Fe1.896Zn0.104O2.948 BNWs sensor up to 45.556 for Fe1.938Sn0.062O3.031 BNWs sensor with the increasing metal valence. The high-valence Sn-doping not only decreases the ground state resistance, but also reduces barrier and work function of α-Fe2O3 BNWs, which results in the improved the sensitivity of α-Fe2O3 BNWs.

Fe4N/Fe soft magnetic composites (SMCs) are fabricated by gas nitridation and molding compaction. The magnetic properties of Fe4N/Fe SMCs have been investigated. With increasing nitridation time, the content of the Fe4N phase, coercivity HC and remanent magnetization Mr increase, while saturation magnetization MS decreases. The core loss of Fe4N/Fe SMCs, especially eddy-current loss, is obviously improved with the increase of Fe4N content. The SMCs with higher Fe4N content present lower μ′, μ″, loss tangent and higher μQ product. Moreover, DC-bias performance has also been improved effectively after nitridation. The results suggest nitridation can effectively improve soft magnetic properties at high frequency.

To reuse the spent magnetic MgAl-layered double hydroxide after humic acid adsorption, this work provided a simple calcination method to prepare the magnetic layered double oxide/carbon (Mag-LDO/C) nanocomposite. The characterization results indicated the Mag-LDO/C was a carbonaceous composite with a large number of functional groups and superparamagnetic property. Then the adsorption performance of Mag-LDO/C for heavy metals was studied by batch experiments. The Mag-LDO/C exhibited excellent removal efficiencies for Cd(II), Pb(II), and Cu(II) with maximum adsorption capacities of 386.1, 359.7, and 192.7 mg/g, respectively. The batch sorption data were studied by the pseudo-second-order kinetic equation and the Langmuir isothermal model, and they matched well. According to the zeta potentials, X-ray diffraction patterns, and X-ray photoelectron spectra of Mag-LDO/C after heavy metals adsorption, the interaction mechanisms were ascribed to the precipitation, surface complexation, and electrostatic attraction. After reaction, the solid-liquid separation of Mag-LDO/C could quickly achieve using a magnet. Additionally, the Mag-LDH/C exhibited excellent adsorption capacities in various simulated wastewater and well sorption recyclability, proving the valuable applications of Mag-LDO/C synthesized from spent adsorbent for metal ions removal in actual water environment.

A sensitive photoelectrochemical (PEC) biosensor for determination of alkaline phosphatase (ALP) activity was constructed based on a photo-excited electron transfer strategy. Immobilization of CdTe quantum dots (QDs) on TiO2 nanotube arrays (TNAs), addition of iron (III) and adenosine triphosphate (ATP) in turn can effectively adjust the photocurrent response of TNAs under visible light irradiation due to a photo-excited electron transfer process, and alkaline phosphatase (ALP) activity can be determined for its catalysis toward dephosphorylation of ATP. The preparation of CdTe QDs, construction of TNA/QD PEC biosensor and the mechanism of photo-excited electron transfer are investigated in the present work. Under the optimal experimental conditions, the TNA/QD PEC biosensor shows a low limits of detection (LODs) (0.05 U L-1) and limits of quantification detection (LOQs) (0.15 U L-1), wide linear range from 0.2 to 15 U L-1, and good selectivity towards ALP determination, which has been successfully applied for human serum analysis with good precision (RSD ≤ 5.4%) and high accuracy (recovery rate, 91-112%).

Mesoporous nickel oxides (NiO) and stannum(Sn)-doped NiO nanowires (NWs) were synthesized by using SBA-15 templates with the nanocasting method. X-ray diffraction, transmission electron microscope, energy dispersive spectrometry, nitrogen adsorption/desorption isotherm and UV–vis spectrum were used to characterize the phase structure, components and microstructure of the as-prepared samples. The gas-sensing analysis indicated that the Sn-doping could greatly improve the ethanol sensitivity for mesoporous NiO NWs. With the increasing Sn content, the ethanol sensitivity increased from 2.16 for NiO NWs up to the maximum of 15.60 for Ni0.962Sn0.038O1.038, and then decreased to 12.24 for Ni0.946Sn0.054O1.054 to 100 ppm ethanol gas at 340 °C. The high surface area from the Sn-doping improved the adsorption of oxygen on the surface of NiO NWs, resulting in the smaller surface resistance in air. Furthermore, owing to the recombination of the holes in hole-accumulation lay with the electrons from the donor impurity level and the increasing the body defects for Sn-doping, the total resistance in ethanol gas enhanced greatly. It was concluded that the sensitivity of Sn-doped NiO NWs based sensor could be greatly improved by the higher surface area and high-valence donor substitution from Sn-doping.

Oyama sinensis is a large deciduous shrub endemic to Sichuan Province, China. Here, we assembled and characterized the complete chloroplast genome of O. sinensis using Illumina sequencing data. Our...

In this paper, nickel oxides (NiO) and iron (Fe)-doped NiO nanowires (NWs) with the various doping content (from 1 to 9 at%) were synthesized by using SBA-15 templates with the nanocasting method. All samples were synthesized in the same conditions and exhibited the same mesoporous-structures, uniform diameter, and defects. Mesoporous-structures with high surface area created more active sites for the adsorption of oxygen on the surface of all samples, resulting in the smaller surface resistance in air. The impurity energy levels from the donor Fe-doping provided electrons to neutralize the holes of p-type Fe-doped NiO NWs, which greatly enhanced the total resistance. The comparative gas-sensing study between NiO NWs and Fe-doped NiO NWs indicated that the high-valence donor Fe-doping obviously improved the ethanol sensitivity and selectivity for Fe-doped NiO NWs. And Ni0.94Fe0.06O1.03 NWs sensor presented the highest sensitivity of 14.30 toward ethanol gas at 320 °C for the high-valence metal-doping.

The magnetic Co3O4 nanowires were synthesized using the templates of SBA-15, and then the well-dispersed nanowires (D-wires) were separated from the bundled ordered nanowires (B-wires) with the centrifugal technique. TEM images indicated that D-wires were highly dispersed Co3O4 nanowires and B-wires existed in bundles. All samples possessed the antiferromagnetism and superparamagnetism at high temperature. After revealing the intrinsic magnetic properties of Co3O4 nanowires with D-wires, the magnetic behavior of B-wires was discussed in detail, and then the magnetic interaction between neighboring nanowires could be deduced. The exchange bias effect from the body Co3O4 antiferromagnetism and surface ferromagnetism was observed at low temperature. The magnetization of B-wires was higher than that of D-wires, which was attributed to the constraint of the surface spin coupling between the neighboring nanowires to the surface affect of nanostructures.

Typical synthesis of α″-Fe16N2 nanoparticles involves nitridation of iron nanoparticles obtained from the reduction of iron oxide, during which the iron nanoparticles are prone to agglomerate and make the nitridation difficult. Herein, we report a method to obtain α″-Fe16N2 phase by loading the iron oxide (hematite, α-Fe2O3) precursors in the channels of the ordered mesoporous silica (SBA-15), and the α-Fe2O3/SBA-15 was prepared by means of a facile impregnation and calcination method. The results showed that the nitridation efficiency was greatly improved than previous reports and high α″-Fe16N2 content (∼92 wt%) was synthesized at 160 °C for 8 h. Transmission electron microscopy and N2 adsorption-desorption characterizations demonstrate that the as-synthesized α″-Fe16N2/SBA-15 nanocomposites maintained the ordered hexagonal mesoporous structures, and α″-Fe16N2 was successfully filled inside the mesochannels of SBA-15, indicating the SBA-15 has taken great effect in the remarkable increasement of nitridation efficiency.

Magnetic cobalt ferrites (CoFe2O4)/activated carbon (AC) nanocomposites were prepared by the hydrothermal method, and then the catalysis for potassium hydrogen persulfate (PMS) to degrade methylene blue (MB) was investigated. The results indicated that 9 wt% CoFe2O4 nanoparticles supplied the sufficient magnetic response for magnetic separation and activated PMS to generate SO4− radicals. The pore-structures of AC could adsorb the residual MB in high concentration near CoFe2O4 catalysts, and promoted MB degradation with SO4− radicals. CoFe2O4/AC nanocomposites presented the good stability and reusability. It was proved that the synergistic effect of PMS and CoFe2O4/AC nanocomposites could greatly improve the MB removal to 100% at the optimized conditions for 60 min.

Ceria nanorods modified with 5,10,15,20-tetrakis(4-carboxyl phenyl)-porphyrin (H2TCPP) were prepared. These nanocomposites (H2TCPP-CeO2) exhibited the intrinsic peroxidase-like activity and could catalyze the oxidation of classical peroxidase substrate 3,3',5,5'-tetramethylbiphenyl dihydrochloride (TMB·2HCl) in the presence of H2O2 to produce a typical color reaction from colorless to blue. Our results demonstrated that both the H2TCPP-CeO2 nanocomposites and CeO2 nanorods exhibited higher thermal durance than that of HRP. The affinity of The H2TCPP-CeO2 nanocomposites toward H2O2 and TMB is similar to that of HRP. Fluorescent results indicated that the catalytic mechanism of the H2TCPP-CeO2 nanocomposites were from the decomposition of H2O2 into hydroxyl radicals. Based on these studies, a simple, sensitive, and selective visual and colorimetric method using TMB as the substrate was designed to detect glucose when combined with glucose oxidase. The proposed colorimetric method can detect H2O2 at a low detection limit of 6.1×10(-6)M and a dynamic range of 10(-5)-10(-4)mol·L(-1). This method can also detect glucose at a low detection limit of 3.3×10(-5)mol·L(-1) and a dynamic range of 5.0×10(-5)-1.0×10(-4)mol·L(-1).

By applying external stimulus (temperature or magnetic field), MnCoGe-based compounds undergo a martensitic transformation from hexagonal Ni2In-type to orthorhombic TiNiSi-type structure accompanied with a giant negative thermal expansion, which suggests a large magnetic-field-induced strain. However, these compounds naturally collapse into powders and are difficult to be oriented, which hinder their applications for magnetostrain. In this paper, a magnetic-field-aligned Mn0.965CoGe compound was prepared by bonding with epoxy resin and orientating in a magnetic field. The XRD patterns revealed the texture in this sample. By introducing vacancies of Mn element, the magnetostructural transformation temperature of Mn0.965CoGe compound was shifted down to 278 K. The magnetostrain was measured at some selected temperatures and the maximal strain could reach up to 925 ppm at 270 K.

NiZn ferrites were selected as coating agents to prepare NiZn/FeSiAl soft magnetic composites (SMCs) in order to improve the soft magnetic property. It is based upon the higher permeability of magnetic NiZn ferrites than that of traditional nonmagnetic coatings, and also relative higher resistance than that of MnZn ferrites. The effects of molding pressure, annealing temperature, and content of insulation on the magnetic properties were studied. As molding pressure increases, the effective permeability increases firstly and then decreases, while the core loss shows a reverse trend, and both get the best performance at 1.6 GPa. With increasing temperature, the permeability increases, reaches the maximum value at 660 °C and then decreases, while the core loss has a reverse trend, and both get the minimum value at 700 °C. The permeability increases with increasing NiZn from 0.1% to 3%, and then decreases. The D-C bias property of FeSiAl SMCs increases with increasing both mica and NiZn content. The larger resistance of mica also causes the better D-C bias property.

α″-Fe16N2 nanoparticles were produced from starting Fe3O4 powders via hydrogen reduction and low temperature nitridation. Influences of both reduction and nitridation conditions on the synthesis of α″-Fe16N2 were investigated in detail. The magnetic properties of the nitrided products were also studied. The results show that the combination of 4-h reduction at 400 °C and 16-h nitridation at 170 °C gives the highest yield of α″-Fe16N2 up to 59.8 wt. %, which exhibits a saturation magnetization of about 207.3 emu/g.