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Ultrafine theta-Al2O3 (θ-Al2O3) nanowires with average diameters of sub-10 nm and lengths up to several micrometers have been successfully synthesized via a novel two-stage method. With temperature gradually elevated, θ-Al2O3 was generated from the slow transformation of gamma-phase Al2O3 (γ-Al2O3), and its ultrafine nanowire structure was formed from the recrystallization of γ-Al2O3 nanowire. By means of nitrogen adsorption–desorption isotherm at 77 K and the multipoint Brunauer–Emmett–Teller (BET) method, the specific surface area of the ultrafine θ-Al2O3 nanowires is found to be up to~120 m2/g. With the high surface area, the material displays excellent gas absorption ability. Hydrogen absorption capacities could be measured to be~5.57 wt% at 77 K (liquid nitrogen), 1.51 wt% at 298 K (room temperature) and 0.81 wt% at 557 K, when a pressure of 30 atm (~3 MPa) is applied. The crystal or chemical nature of metastable θ-Al2O3 phase may play a vital role in the observed excellent gas storage capacity.

The martensitic transformation in Heusler alloy Mn2PtIn has been investigated by first-principles calculations and experimental studies. Theoretical calculation reveals that, in Mn2PtIn, a transition from cubic structure to tetragonal one is favorable in energy. This has been confirmed by following experimental studies. At room temperature, Mn2PtIn crystallizes in a tetragonal structure of the space group I-4m2. And a transition from tetragonal to cubic Heusler phase occurs at 638 K. Mn2PtIn is a ferrimagnet in both austenitic and martensitic phases. Its magnetic properties are mainly determined by the antiparallel aligned Mn spin moments. These findings can greatly enlarge our scope of discovering new FSMAs in Heusler alloys containing 4d and 5d elements. (C) 2013 Elsevier Ltd. All rights reserved.

Boron carbon oxynitride (BCNO) phosphors with wide excitation and emission range (up to 630 nm emission peak) were prepared at 675 °C under atmospheric pressure. Boric acid, melamine and glycerol were used as boron, nitrogen and carbon sources, respectively. The BCNO phosphor had turbostratic structure (t-BCN) and particle size was in the range of 10–50 μm. FTIR results indicated that the and O were involved in the structure of samples and bonded to B and N to form BCNO phosphors. Both the excitation and emission spectra shifted to long wavelength and the emission peak position can be tuned from 460 nm to 630 nm with increasing glycerol. Ultraviolet–visible absorption spectra suggested that optical band gap of BCNO phosphors decreased with increasing glycerol. The spectra properties were closely related to the carbon related defects levels.

The electronic structure and magnetism of Heusler alloys Mn2NiGe and Ni2MnGe have been studied by first-principles calculations. The possible non-modulated tetragonal martensitic transformation in them has been predicted. For both Mn2NiGe and Ni2MnGe, the tetragonal martensitic phase is lower in energy compared with the cubic austenitic phase. In Ni2MnGe, the martensitic transformation follows the conservation of volume. But in Mn2NiGe, a small contraction of the martensitic cell volume is predicted. The energy difference DE between the martensitic and austenitic phase is � 8 meV/cell in Ni2MnGe and � 80 meV/cell in Mn2NiGe, so it is more likely to observe martensitic transformation in Mn2NiGe or Heusler alloys with similar compositions. Ni2MnGe is found to be a ferromagnet, while Mn2NiGe is a ferrimagnet in which the Mn spin moments are in antiparallel coupling.

The electronic structure and magnetic properties of Fe-based binary half-Heusler alloys Fe 2 Z (Z=In, Sn, Sb and As) have been studied. It is found that binary Fe 2 Z has a site preference similar to normal ternary ones. Hybridization between the d states of Fe (A) and Fe (B) leads to the formation of a d–d band gap near E F . This gap is broadened and shifted to low energy as Z varies from In to Sb, which makes Fe 2 Sb a half-metal. The half-metallicity of Fe 2 Sb is insensitive to the lattice distortion. The spin polarization ratio is always 100% from 5.6 A to 6.2 A. The spin polarization of Fe 2 As is also high at equilibrium lattice constant. With a small expansion of the lattice, it becomes an ideal half-metal. Fe 2 Z alloys are all ferromagnets with parallel aligned Fe spin moments.

BCNO phosphors with tuneable emission spectra were prepared at 625 °C under atmosphere using boric acid, melamine and glucose as raw materials. The XRD, SEM and FTIR results show that the prepared compound is composed of cubic B2O3 and partially crystalline BCNO. The emission peak position can be tuned from 510 nm to 560 nm by changing the glucose contents and the mol ratios of boric acid and melamine. The decay process of BCNO phosphors can be fitted well by double exponential function, and the lifetimes τ1 and τ2 were correlated with carbon impurity concentration and other defects in BCNO phosphor, respectively.

To develop high performances of inorganic fibers/polymer composites, the interfacial interaction and dispersal of fibers are the two essential issues to be considered. Herein, we report the surface decoration of basalt fibers (BF) with hybrid Fe3O4 microspheres (FePc–Fe3O4) and their microwave absorption application in bisphthalonitrile composites was systematically investigated. Firstly, the hybrid Fe3O4 microspheres with a diameter of ∼140 nm were self-assembled onto the basalt fibers via a simple solvothermal route, as confirmed by SEM and TEM observations. The obtained BF (FePc–Fe3O4–BF) displayed magnetic performance with excellent interfacial adhesion application. Secondly, the FePc–Fe3O4–BF reinforced bisphthalonitrile composite laminates were studied for improvement in their microwave absorption, mechanical and thermal properties through strategically incorporating the FePc–Fe3O4 microwave absorber at the fiber/fabric–matrix interfaces. The calculated reflection losses showed that the best microwave absorption reached −31.1 dB at 5.9 GHz with a matching thickness of 5 mm. The results indicated that investigation of the decoration of basalt fibers and the addition of a special microwave absorber opened up a new route to develop the composite laminate as a promising candidate for microwave absorbing materials in high-temperature applications. Besides, we found that the FePc–Fe3O4–BF reinforced bisphthalonitrile composite laminate, with excellent thermal stability, revealed an approximately 189% increase in flexural strength and also offers better microwave absorption compared to that of the BF reinforced bisphthalonitrile composite laminate.

Pancreatic cancer is one of the leading causes of cancer-related death worldwide. Activating transcription factor 2 (ATF2) is a multifunctional transcription factor, and is implicated in tumor progress, yet its role in pancreatic cancer remains unclear. In the present study, the level of ATF2 in pancreatic cancer tissues and the adjacent non-tumorous tissues was detected by quantitative real-time PCR and Western blot. The roles of ATF2 in the proliferation, cell cycle, and apoptosis of pancreatic cancer cells were investigated through ATF2 silencing, and the effect of ATF2 shRNA on the sensitivity of pancreatic cancer cells to gemcitabine, an anti-tumor drug, was explored. The results of our study showed that the ATF2 level in the pancreatic cancer tissues was higher than that in the adjacent non-tumorous tissues. Silencing of ATF2 was found to inhibit proliferation, arrest cell cycle at G1 phase and induce apoptosis in pancreatic cancer cells. Moreover, ATF2 silencing enhanced gemcitabine-induced growth-inhibition and apoptosis-induction effects in pancreatic cancer cells. In summary, silencing of ATF2 inhibited the growth of pancreatic cancer cells and enhanced the anti-tumor effects of gemcitabine, suggesting that ATF2 plays a pro-survival role in pancreatic cancer. Our results also propose that a high level of ATF2 may serve as a potential biomarker of pancreatic cancer, and that ATF2 may become a potential target for anti-tumor therapy.

Ammonium polyphosphate (APP) was encapsulated with boron-modified phenolic resin (BPF) by in situ polymerization with the goal of improving its hydrophobicity, thermal stability, and compatibility in polymers. The chemical and physical features of APP microcapsules were characterized by Fourier transform infrared, X-ray photoelectron spectroscopy, scanning electron microscopy, inductively coupled plasma, and laser particle sizing. The hydrophobicity was assessed by the water contact angle. The residues from thermogravimetric analyzer and muffle burner were investigated. The results showed that the APP microcapsules with BPF shell had been achieved successfully. The shell encapsulation rate mainly depended on the amount of crosslinking agent when the ratio of APP/BPF was constant. The mean particle size increased and the particle size distribution became more narrow. The hydrophobicity of APP was improved and the improvement degree mainly depended on the amount and adding rate of crosslinking agent and the conditions of heat curing. A good thermal stability and high residue char rate at high temperature were noticed for APP microcapsules. It suggests that these microcapsules might be used as an intrinsic flame retardant. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43720.

Two new double-sided and multi-layered network porous compound named 1 [Ni2(BTC)2(DABCO)(DEA)2] have been synthesized by solvent thermal synthesis method. Which, for the first time, exhibit an unusual double-sided and multi-layered MOF. The double-sided MOF structure extended to regular hexagon morphology in accordance with schematic representation of the 2D topological net of 1 and also confirmed by the SEM images. The N2 and H2 sorption certified it can be used as gas absorption. Introduction Porous metal–organic frameworks (MOFs) also known as porous coordination polymers, are crystalline coordination networks consisting of metal ions/clusters and organic linkers, are currently under intensive investigation because of their rich structural chemistry and outstanding properties, regarding not only the specific surface area and storage capacities, but also the flexibility of the framework. The systematic design and construction of coordination polymers by using organic molecular building blocks and metal ions appeared in the early half of the 1990s, More than 20000 MOF structures have been reported and studied since then. In 1999, two archetypical MOFs, MOF-5(Zn4O(bdc)3, bdc=terephthalate) and HKUST-1(Cu3(btc)2, btc=1,3,5-benzenetricarboxylate) were synthesized and characterized, symbolizing a benchmark in MOF chemistry with their high porosity indicated by crystal structures and confirmed by low pressure gas sorption studies. A key structure feature of MOFs is the ultrahigh porosity (up to 90% free volume) and incredibly high internal surface areas, extending beyond a Langmuir surface area of 10000 m g, which play a crucial role in functional applications, typically in storage and separation, sensing, proton conduction and drug delivery. One of the most interesting features of MOFs is that frequently their structure can be deduced from the directionality of organic linkers and the coordination geometry of metal building blocks. In this way, MOFs can be engineered to a large extent and can be synthesized by design with the desired structure and dimension. In this regard, we have constructed a new Two-Dimensional multi-layered Network porous compound named 1 [Ni2(BTC)2(DABCO)(DEA)2], (Nickel nitrate hexahydrate H3btc=1,3,5-benzenetricarboxylate acid(Bridge ligand), DABCO=1,4-diazabicyclo[2.2.2]octane ( Auxiliary ligand ) , DEA =Diethylamine) by using rigidly designed carboxylate ligands in solvent thermal synthesis method, which, for the first time, exhibit an unusual double-sided and multi-layered MOF. The N2 sorption isotherms show that it has a large Brunauer–Emmett–Teller (BET) surface area and pore volume. In its structure, Ni atoms to adopt irregular quadrilateral double-heap coordination model. Every Ni atoms coordinated with four O atoms(two come from one bivalent carboxylic group of one btc,(two O atoms are in mono dentate coordination come from two monobasic carboxylate O ions of two btc ligand in a planar separately),the two pairs of O atoms form a square-planar coordination around 2nd International Conference on Machinery, Materials Engineering, Chemical Engineering and Biotechnology (MMECEB 2015) © 2016. The authors Published by Atlantis Press 761 the Ni atom (Figure 1. a)). DABCO as bridging ligands, which act as pillars to extend the double-sided 2D layers (Figure 1. b)). The DABCO pillar molecules, which occupy the axial positions of the [Ni2(BTC)2(DABCO)(DEA)2] paddle-wheels, the double-sided 2D layers structure further interconnect and extend into a multi-layered architecture by Van der Waals force and H-bond interaction(Figure 1. e)). Two N atoms axially coordinated to one Ni come from DABCO and DEA. The four O atoms form a planar coordinated around the central Ni atom, Axis of N-Ni-Ni-N perpendicular to the planar, the six Ni atoms build up a isosceles triangular prism constructure. The bonds length of Ni-O are 2.1873 A and 2.0594 A, The bonds length Ni-N are 2.0913 A and 2.1811 A separately. The Ni...Ni distance connected by a ligand DABCO are of 6.9590 A. Figure 1. a) the coordination modes of six-connected Ni2(BTC)2(DABCO)(DEA)2 SBUs; b) a isosceles triangular prism in 1; c) View of the porous framework of 1 viewed close to [100] direction; d) schematic representation of the 2D topological net of 1 (viewed close to the [100] direction; green connection point representing the dummy node of triangle plane(three Ni) of a isosceles triangular prism; e) View of the multi-layered porous framework of 1 viewed close to [010] direction; f) Schematic representation of the formation of Ni2(BTC)2(DABCO)(DEA)2. Experimental Section. Chemicals were purchased from commercial sources and used without further purification. Powder X-ray diffraction (PXRD) was carried out with an X-ray diffractometer of Rigaku, Rint 2000. C, H, and N elemental analyses were conducted on a Perkin–Elmer 240C elemental analyzer. Thermo gravimetric analyses (TGA) were carried out on a Perkin–Elmer TG-7 analyzer heated from room temperature to 873 K at a ramp rate of 5 K/min under nitrogen. The N2 and H2 sorption measurements were performed on automatic volumetric adsorption equipment (Belsorp mini II). Before gas adsorption measurements, the sample was treated with ethanol and dichloromethane. Before the measurement, the sample was dried again by using the “outgas” function of the surface area analyzer for 12 h at 393 K. The data were collected by using graphite-monochromatized enhanced ultra Cu radiation at 293 K. The data sets were corrected for empirical absorption correction by using spherical harmonics, as implemented in the SCALE3 ABSPACK scaling algorithm. The structures of the compound 1 were solved by direct methods and refined by full-matrix, least-square methods with the SHELX-97 program package. Determinations of the unit cells and data collection for crystal of 1 were performed on an Oxford Xcalibur Gemini Ultra diffractometer with an Atlas detector. The solvent molecules in the compound are highly disordered, and the SQUEEZE subroutine of the PLATON software suite was used to remove the scattering from the highly disordered guest

Oxalate-loaded microcapsules can be used as applicablecatalyst ofin-situ heat system for hydraulic gel fracturing. In this study, oxalate-loaded microcapsulewas prepared with AS as the shell material via phase separation. The product was characterized by thermogravimetric analyzer (TGA), laser diffraction particle size analyzer, and in vitro-release experiment. The test results indicate that the product obtained was particles composed of oxalate and acrylonitrile-styrene copolymer (AS) with the average particle size of 122.0 μm and sustained-release performance.

Ammonium polyphosphate (APP) was encapsulated with different cross-linked structure tung oil phenolic resin(TPF) by in situ polymerization and it was performed that a study on the influence of the cross-linking agent type on the hydrophobicity of the APP microcapsules.The chemical and physical features of APP microcapsules were characterized by Fourier transform infrared(FTIR), X-ray photoelectron spectroscopy(XPS). The hydrophobicity was assessed by the water contact angle(WCA). The results showed that the APP microcapsules with different cross-linked structure TPF shell had been achieved successfully and the cross-linking agent type had important influence on the hydrophobicity of APP microcapsules.

The behavior of acoustic modes in solids can yield information on the glass dynamics at different length and frequency scales. Inelastic X-ray scattering (IXS) using Synchrotron radiation allows us to obtain detailed information on the sound speed behavior at different length scales as well as approaching the macroscopic limit. This gives an insight to the microscopic mechanisms responsible for the mechanical properties in the THz frequency domain. IXS also provides a method to investigate the fragility of glass-forming liquids via the non-ergodicity factor of the corresponding glasses. Moreover, some questions arise about how phenomena such as the polyamorphism, observed, e.g. in Ce55Al44 upon application of pressure, affect the mechanical properties of a metallic glass at a microscopic level. In this article we reveal a change in the high frequency response at the mesoscopic length scale with respect to the ultrasounds limit in metallic glasses. We will also review further applications of IXS on Pd and Ce-based metallic glasses to determine elastic constants, changes in sound speed due to polyamorphism and to investigate their fragility. (C) 2012 Elsevier Ltd. All rights reserved.

The electronic structure and magnetic properties of new Fe-based Heusler alloys Fe(2)TiZ (Z = Ga, Ge, As, In, Sn and Sb) have been studied by first-principles calculations. In these alloys, the 24-electron Fe2TiGe, Fe2TiSn are nonmagnetic semiconductors and other compounds are all ferrimagnetic metals. Fe2TiAs and Fe2TiSb are predicted to be half-metals with 100% spin polarization. The spin polarization ratio in Fe2TiGa and Fe(2)Tiln is also quite high. The calculated total moment for Fe2TiAs and Fe2TiSb is 1 mu(B), which is mainly determined by the Fe partial moment. The half-metallicity of Fe2TiSb is stable under lattice distortion. The spin polarization of Fe2TiSb is found to be 100% for the lattice variation in a range of 5.6-6.1 angstrom, which is attractive in practical applications. (C) 2012 Elsevier B.V. All rights reserved.

A new white Ca3 − xSi2O7: xDy3+ (x = 0.03, 0.05, 0.07, 0.10) phosphor with various Dy3+ concentrations was prepared and its photoluminescent properties were investigated. The XRD results show that the Dy3+ substitution of Ca2+ does not change the structure of Ca3Si2O7 host for x ≤ 0.10. The SEM image displays that phosphors aggregate obviously, and the shape of the phosphor particle is irregular. The EDX results reveal that the phosphors consist of Ca, Si, O and Dy elements. Luminescence spectra excited by 350 nm consist of two characteristic blue and yellow bands, which correspond to 4F9/2→6H15/2 and 4F9/2→6H13/2 transitions of Dy3+, respectively. The yellow-to-blue emission intensity ratio under excitation of 350 nm increases with the elevated Dy3+ concentrations, and the evaluated color coordinates of the investigated samples fall in the white light region. The energy transfer style between Dy3+ ions is dipole–dipole interaction for higher concentration Dy3+ doped Ca3Si2O7 phosphor. The quantum efficiency for x = 0.05 sample excited by 365 nm is 15.16%.

We firstly report an efficient and novel method to functionalize graphene with 4-aminophenoxyphthalonitrile and successfully compound them with poly(arylene ether nitrile) (PEN) to prepare nanocomposite films. Fourier transform infrared spectra (FTIR), Raman spectra, and atomic force microscopy (AFM) were employed to examine the surface functionalization of graphene. The resulting PEN nanocomposite exhibited significant increase in dielectric permittivity. For 3 wt.% nitrile functionalized graphene reinforced PEN nanocomposite film, the dielectric constant increased from 3.2 to 17.8 at the frequency of 1 kHz. In addition, the PEN nanocomposite films showed low dielectric loss and good flexibility. This opens a new route to optimize interface structures and improve the comprehensive performances of graphene–polymer nanocomposites.

The origin of the Slater–Pauling curve M t = Z t −28 (Here M t is the total spin moment and Z t is the number of valence electrons) in half-metallic Heusler alloys Mn 2 CuZ (Z=Ge and Sb) has been studied in detail. In Mn 2 CuZ the half-metallic gap has a similar origin like half-Heusler alloys. The Cu atom acts as an electron “donator” in Mn 2 CuZ, which contributes five d -electrons to the minority spin band of Mn 2 CuZ. So there are 14 valence electrons in the minority band of Mn 2 CuZ below the Fermi level. This is the origin of the S – P curve M t = Z t –28. Finally, it is found that, by partial doping of Cu to the vacant site of half-metallic half-Heusler alloys, the magnetic moments of these can be tuned without destroying the half-metallicity. This can be a possible way to design new half-metals.

Novel hybrid nanospheres composed of organic magnetic resin and Fe3O4 (OMR/Fe3O4) were prepared via an effective solvothermal route. The morphology and structure of the hybrid nanospheres were characterized by Fourier transform infrared spectrophotometer (FTIR), scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). These results showed that the as-prepared nanospheres were well-defined in size (200–230 nm) and shape. Base on these results, the formation process was discussed. Magnetization measurement showed that the saturation magnetization and coercive force of the hybrid nanospheres were 62.6 emu g−1 and 163.5 Oe at 300 K, respectively. The microwave absorption properties were measured by a vector network analyzer and the data indicated that the addition of organic magnetic resin has greatly affected the microwave electromagnetic properties of the hybrid nanospheres. The as-prepared hybrids displayed different electromagnetic properties from conventional nano-Fe3O4 particles. The loss in magnetism exhibited two obvious peaks: one appeared at 4.0–5.0 GHz, the other sharp peak appeared around 9.0–12.0 GHz. The former peak was attributed to the natural properties of the Fe3O4 and the latter was owing to the interface effects between OMR and Fe3O4 particles.

Poly(arylene ether nitrile) (PEN) nanocomposites filled with functionalized graphite nanoplates (GNs) were prepared by a simple solution- casting method and then characterized by rheometer and thermogravimetric analysis (TGA). This study investigates how the surface treatment of GNs affects the GN dispersion state. The linear rheological test indicated that the 4-aminophenoxyphthalonitrile-grafted GN (GN-CN) presented better dispersion in PEN matrix than purified GN because the corresponding composite showed the lower rheological percolation threshold, which was further confirmed by scanning electron microscopy and solution experiments. The TGA revealed that the presence of 4-aminophenoxyphthalonitrile-grafted GN retarded the depolymerization evidently compared with that of purified GN, showing remarkable increase in the temperatures corresponding to a weight loss of 5 wt % (increased by 21°C) and maximum rate of decomposition (increased by 9°C). Both the dispersion state and the surface functionalization of GN are very important to the thermal stability of PEN matrix. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

The carboxylic poly(arylene ether nitrile)/Fe 3 O 4 hybrid microspheres were prepared via solvothermal method. The carboxylic poly(arylene ether nitrile) (PEN-COOH) was introduced into the Fe 3 O 4 microspheres by chemisorption with mass content up to 15% as defined by infrared spectra and thermal gravimetric analysis. The hybrid sphere is of hierarchical polymer–inorganic microstructure as observed by transmission electron microscopy. The microwave-absorption of the sample owns a shifting peak and a special immobilized peak with the variation of absorber thickness from 3 to 5 mm. Maximum microwave-absorption of the product is capable of over −30 dB in the range of 10–12 GHz. By proposed equivalent filter circuit model, the immobilized peak was attributed to the ordered nanostructure where the Fe 3 O 4 nanocrystals were isolated by PEN-COOH. The product has the potential to be applied as microwave absorber with high microwave-absorption, good dispersibility and robust polymer–inorganic interfacial adherence.

Fe 3 O 4 /CuPc hybrid material, where the CuPc not only interlinked but also be embedded within the Fe 3 O 4 microspheres, was synthesized via solvothermal method. The electromagnetic properties of the sample showed cooperative nonlinear dielectric/magnetic resonance in X-band and Ku-band. The proposed equivalent filter circuit model well explained the dual nonlinear dielectric resonances. The magnetic resonances were proposed to be generated from the natural resonance of the Fe 3 O 4 and heterogeneous interfaces in/between microspheres severally. The microwave absorption of the sample obtained two optimal nesting peaks of − 35 and − 33 dB at 12.6 and 15.8 GHz with thickness of 2.6 and 1.8 mm respectively.

In this work, we report a new strategy of introducing thorns-like fiber into composites, so that the resultant composites substantially benefit from strong fiber–matrix interface adhesion. Specifically, the “thorns” could increase in interlocking molecules chains and entangle with the surrounding matrix resin, which could impede the mobility of polymer chains, as like the roots with uplift capacity. Strong interfacial adhesion between fibers and matrices is suggested by the SEM images and the DMA studies. After the thorns-like fibers are embedded into epoxy resin, the glass transition temperature ( T g ) and the storage modulus ( E ′) are higher than these of neat epoxy and untreated fibers-reinforced epoxy, respectively, and the flexural properties of the composites reinforced with thorns-like fibers are significantly increased. Therefore these novel three dimensional thorns-like fibers will be applicable for composite materials based upon its unique architecture, making it an attractive alternative to increase the performance of any matrix resin.

To provide a new way to fabricate novel wave-adsorbing material, ferrocenyl organic metal magnetic resin (FOMR) was successfully prepared from ferrocenyl bisphthalonitrile via an effective and mild solvent-thermal route. The structure analysis of as-synthesized FOMR was performed using Fourier transform infrared spectrophotometer and ultraviolet–visible absorption spectrum. Magnetic behavior of the sample were also studied by vibrating sample magnetometer and the experimental results indicated that the magnetic material were ferromagnetic with maximum saturation magnetization of 1.3 emu g− 1 at 300 K. Measurements of electromagnetic parameters of FOMR show that the maximum absorbing peak has a bandwidth of 7.0 GHz (RL < 4 dB). The specific gravity of FOMR was about 0.86. On the basis of these results, the novel magnetic materials are believed to have potential applications in the microwave absorbing area and in biomedical field.

An efficient method was developed to fabricate a porous hybridizing nanotubes structure of amorphous carbon interspersed among Fe3O4 (C@Fe3O4) with a ∼200 nm diameter and ∼70 nm wall thickness. The as-structured porous nanotubes with ferromagnetic behaviour exhibited excellent microwave absorption properties, including a strong ability to attenuate the electromagnetic (EM) wave, and they are also lightweight. Adding only 10 wt% of the as-prepared sample into paraffin can show a maximum reflection loss of −45.0 dB at 6.18 GHz with a sample thickness of 3.4 mm. The absorption mechanism, which results from its porous nanotubes structure, multi-interfaces, dielectric–magnetic integration and geometric effect, is proposed to explain the excellent EM absorption performance. Furthermore, the synthesis strategy presented herein can be expended as a facile approach to synthesizing related carbon-based nanostructures for functional design and applications.

Novel organometal/Fe 3 O 4 hybrid microspheres were prepared from bisphthalonitrile-benzoxine resin containing ferrocene (FPNBZ) and FeCl 3 ·6H 2 O via a one-step solvent-thermal method. The phase structure, composition and morphology of as-prepared hybrid microspheres were characterized by X-ray powder diffraction, Fourier transform infrared spectrophotometer and scanning electron microscopy. The results revealed that crystallinity, dispersity and size of hybrid microspheres can be controlled by altering the reaction parameters. Density measurement showed that the density is decreased with increasing FPNBZ concentration in the hybrid materials. Electromagnetic properties of the FPNBZ/Fe 3 O 4 hybrid microspheres were measured at 2–18 GHz. The electromagnetic measurement indicated that the resonance peaks of complex permittivity, complex permeability, dielectric loss and magnetic loss were shifted to the high frequencies, with the increasing amount of FPNBZ. The as-prepared hybrid materials are believed to have broad applications both in microwave absorption materials in a wide frequency range and in biomedical fields.

Ab initio calculation have been carried out to investigate the electronic structure and magnetism of the compound Mn2Sn with the bcc half-Heusler structure. For the equilibrium lattice parameter 5.69 angstrom, Mn2Sn is predicted to be a half-metallic fully compensated ferrimagnet (also called half-metallic antiferromagnet) with zero total spin moment. This zero moment agrees well the Slatter-Pauling curve and mainly comes from the compensated Mn (A) and Mn (B) spin moments in antiparallel configuration. The half-metallicity of Mn2Sn is stable in a wide lattice-parameter range from 5.6 angstrom to 5.9 angstrom. Upon contraction of the lattice, a transition from half-metallicity to semimetallicity is observed. (C) Elsevier B.V. All rights reserved.

Our main goals in this work were to fabricate and characterize a novel magnetic composite of graphene nanosheets and poly(arylene ether nitrile) (magnetite-GNs/PEN). Fabrication was achieved through two steps. First, covalent deposition of magnetite nanoparticles on the GNs surface in the presence of iron (III) chlorides and GNs in a solvothermal process resulted in the fabrication of the magnetite-GNs hybrids. Second, loading of the as-prepared hybrids over poly(arylene ether nitrile) (PEN) through solution-casting method afforded the magnetic composite (magnetite-GNs/PEN). Scanning electron microscope (SEM) and transmission electron microscopy (TEM) observations indicated that magnetite nanopatarticles with the sizes of 30–50 nm evenly spread over the GNs surface via covalent bond, which was confirmed by X-ray diffraction (XRD), Fourier transform infrared (FTIR) characterization and X-ray spectrometer (EDS). The mechanical properties and thermal stability of magnetite-GNs/PEN nanocomposites were significantly enhanced by incorporation of magnetite-GNs hybrids. Finally, improvement of the PEN properties by its loading with magnetite-GNs hybrids was established through our preliminary vibrating sample magnetometer (VSM) and rheological analyses.

Bulk production of iron nanowire inside carbon nanotubes (CNTs) from iron phthalocyanine (FePc) polymer under 800 °C is presented for the first time. The bis-phthalonitrile was firstly reacted with iron nanoparticles to produce iron phthalonitrile oligomer, and heat treatments made the formation of CNTs occurred during the carbonization process of FePc polymer at ambient pressure in nitro atmosphere under 800 °C. The iron nanowire inside carbon tubes from the metal Pc polymer possessed excellent electromagnetic loss and magnetic loss properties.

Novel functionalized graphene sheets (FGSs)/Fe3O4 hybrids were synthesized through a facile one-step solvothermal method using FeCl3 as iron source, ethylene glycol as the reducing agent and graphene nanosheets as templates. The morphology, composition and phase structure of as-prepared hybrid materials were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and transmission electron microscopy (TEM). These results showed that denseness, size and crystallinity of magnetite can be altered by controlling the reaction parameters. Magnetization measurement indicated that both coercivity and saturation magnetization increased linearly with increasing magnetite concentration in hybrid materials. The measured relative complex permittivity indicated that a high resistivity existed in the FGSs/Fe3O4 inorganic hybrids. The magnetic loss was caused mainly by ferromagnetic natural resonance, which is in agreement with the Kittel equation. The novel inorganic hybrid materials are believed to have potential applications in the microwave absorbing performances.

Quaternary Heusler alloys Fe 1.5 M 0.5 CoSi with M=V, Cr, Mn and Fe have been investigated theoretically and experimentally. All of these samples crystallize in the ordered Heusler-type structure. The calculated electronic structure shows a pseudogap around E F in the minority spin states of Fe 2 CoSi. With the substitution of low-valent atoms for Fe, the majority antibonding peak is shifted to higher energy and a minority gap around the Fermi level is opened. High spin polarization ratio is obtained in Fe 1.5 M 0.5 CoSi (M=V, Cr, Mn) alloys. The calculated total spin moments decrease with decreasing number of valence electrons and follow the Slater–Pauling curve, which agree with the experimental results well. The Curie temperature decreases as M atom varies from Fe to V, but is always higher than 650 K, which is suitable for technical applications.

Novel rose thorns-like nanofibers, composed of polyarylene ether nitriles (PEN) “rose stems” and iron phthalocyanine (FePc) “thorns”, are prepared by combining electrospinning and controlled temperature-induced self-assembly. After removing solvent and subsequent temperature treatment, the FePc sheath structure changes from bead structure to rose thorns-like structure. The unique nanoscale architecture can be finely controlled by the processing time and temperature. The length of “thorns” on the “rose stems” can change from several nanometers to decade micrometers. The driving force for the morphology changes comes from self-assembly of FePc, including the π–π supramolecular interaction between aromatic cores and the cooperative complexation of metal ions between peripheral crown ether moieties. This novel structure, rendering a 3-D feature, can offer potential in a number of applications, including nanoelectronics.

The novel nano-scale iron phthalocyanine oligomer/Fe3O4 (FePc/Fe3O4) hybrid microspheres were synthesized from iron phthalocyanine oligomer and FeCl3·6H2O via a solvent-thermal crystallization route. The morphology and structure of the hybrid microspheres were characterized by Fourier transform infrared spectrophotometer, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. These results showed that the hybrids were monodisperse microspheres and the morphology can be adjusted by controlling pre-polymerization time. The saturation magnetization increased with increase in the pre-polymerization time, while the coercivities decreased. The FePc/Fe3O4 hybrid microspheres exhibited novel microwave electromagnetic properties: the dielectric loss was enhanced when the pre-polymerization time increased and a new microwave loss peak appeared at high frequency. The microwave absorbing properties enhanced with increase in the pre-polymerization time and a maximum reflection loss of −29.7 dB was obtained at 11.7 GHz with 6 h of pre-polymerization time when the matching thickness was 3.0 mm. The novel hybrid materials are believed to have potential applications as microwave absorbing materials.

A novel sandwich-like graphene nanosheets (GNs)/Fe 3 O 4 hybrid material was synthesized through a facile one-pot solvothermal method using FeCl 3 as iron source, ethylene glycol as the reducing agent and graphene nanosheets as templates. The Fe 3 O 4 nanoparticles, with the average diameters of ca. 40 nm, were self-assembled on the graphene nanosheets through electrostatic attraction and formed sandwich-like nanostructure. The ferromagnetic signature emerged with the saturated magnetization of ~ 72.3 emu g − 1 , and the coercive force of ~ 196.1 Oe at 300 K. The magnetic loss was caused mainly by natural resonance which is in agreement with the Kittel equation. The novel electromagnetic hybrid material is believed to have potential applications in the microwave absorbing performances.

Deposited with different oxygen partial pressures and substrate temperatures, MgxZn1−xO thin films were prepared using a Mg0.6Zn0.4O ceramic target by magnetron sputtering. The structural and optical properties of the prepared thin films were investigated. The X-ray diffraction spectra reveal that all the films on quartz substrate are grown along (2 0 0) orientation with cubic structure. The lattice constant decreases and the crystallite size increases with the increase of substrate temperature. Both energy dispersive X-ray spectroscopy and calculated results suggest the ratio of Mg/Zn increases with increasing substrate temperature. The thin film deposited with Ts = 500 °C has a minimal rms roughness of 7.37 nm. The transmittance of all the films is higher than 85% in the visual region. The optical band gap is not sensitive to the oxygen partial pressure, while it increases from 5.63 eV for Ts = 100 °C to 5.95 eV for Ts = 700 °C. In addition, the refractive indices calculated from transmission spectra are sensitive to the substrate temperature. The photoluminescence spectra of MgxZn1−xO thin films excited by 330 nm ultraviolet light indicate that the peak intensity of the spectra is influenced by the oxygen partial pressure and substrate temperature.

Magnetite particles with nanoscale sizes were self-assembled along multiwalled carbon nanotubes through a simple, effective and reproducible solvothermal method. The morphology, composition and phase structure of as-prepared hybrid materials were characterized by scanning electron microscopy, X-ray diffraction and transmission electron microscopy. The results showed that denseness, size and crystallinity of magnetite can be altered by controlling the reaction parameters. Magnetization measurement indicated that both coercivity and saturation magnetization increased linearly with increasing magnetite concentration in the hybrid materials. Electromagnetic properties of the carbon nanotubes/magnetite inorganic hybrid materials were measured at 1∼18 GHz. The magnetic loss was caused mainly by ferromagnetic natural resonance, which is in agreement with the Kittel equation. The as-prepared inorganic hybrid materials are believed to have potential applications in the microwave absorbing area.

The novel nano-scale Fe-phthalocyanine oligomer/Fe 3 O 4 hybrid microspheres were synthesized from bis-phthalonitrile and FeCl 3 ·6H 2 O through a simple solvent-thermal route. The morphology and structure of the hybrid microspheres were characterized by FTIR, XRD, SEM and TEM. These results showed that the hybrids were monodispersed solid microspheres and the morphology can be adjusted by controlling the addition of bis-phthalonitrile. On the basis of these results, the formation process was discussed. Magnetization measurement indicated that saturation magnetizations decreased linearly with increasing the addition of bis-phthalonitrile, while coercivities increased. The microwave absorption properties were measured by a vector network analyzer. The dielectric loss of the hybrid microspheres was larger and a new magnetic loss peak appeared at high frequency. The microwave absorbing properties enhanced with increasing the addition of bis-phthalonitrile and a maximum reflection loss of −31.1 dB was obtained at 8.6 GHz with 1 g bis-phthalonitrile when the matching thickness was 3.0 mm. The novel hybrid materials are believed to have potential applications in the microwave absorbing performances.

In this study, a novel multifunctional poly(arylene ether nitriles)(PEN)/carbon nanotubes/Fe3O4 nanocomposite with high tensile strength, magnetic, and electrical properties was investigated. First, we synthesized the monodisperse Fe3O4 nanoparticles on the surface of the multiwalled carbon nanotubes and then the hybrid material was compounded with PEN through the solution-casting method. The SEM and TEM images indicated that the monodisperse Fe3O4 nanoparticles, with the diameters of 70∼80 nm, were self-assembled along CNTs via the covalent bond method, which was confirmed by FTIR and XRD. The results of tensile properties showed that the tensile strength and modulus reached their highest values at the CNTs/Fe3O4 loading content of 1 wt % and both were greatly enhanced after heat treatment. Electrical conductivity of the polymer was dramatically enhanced at the low loading level of CNTs/Fe3O4; the electrical percolation of was in the range of 5∼8 wt % of CNTs/Fe3O4. The magnetic study showed that the saturation magnetization (Ms) of PEN/CNTs/Fe3O4 nanocomposites increased with the increase of CNTs/Fe3O4 loading content, and the coercive force (Hc) of the nanocomposite was independent of the CNTs/Fe3O4 content. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011

A novel carbon nanotubes/Fe 3 O 4 inorganic hybrid material was prepared by in situ decomposition of the precursor ferric chloride crystal and CNTs in liquid ethylene glycol. XRD, SEM, TEM, EDS were used to characterize the as-prepared products. Results indicated that the monodispersed magnetite microspheres with the size of about 100 nm were uniformly self-assembled along the surface of the carbon nanotubes. The formation of magnetite nanoparticles on CNTs was through an aggregation process of subparticles on the surface of CNTs. The ferromagnetic signature emerged with the saturated magnetization of 60.94 emu g −1 , and the coercive force of 148.59 Oe at 300 K. The measured relative complex permittivity indicated a high resistivity existence in the CNTs/Fe 3 O 4 inorganic hybrid material. The magnetic loss was caused mainly by natural resonance, which is in good agreement with the Kittel equation results. The novel electromagnetic hybrid material is believed to have potential applications in the microwave absorbing performances.

Fe–phthalocyanine oligomer/Fe3O4 nano-hybrid particles were successfully prepared from bis-phthalonitrile and FeCl3·6H2O through a simple and effective solvent-thermal route. The hybrids were monodispersed solid microspheres from the coalescence of small particles. About 3.7% of the phthalocyanine polymer was incorporated into the resulting hybrids. Then the hybrids as nanofillers in polyarylene ether nitriles (PEN) were investigated. The scanning electron microscopy (SEM) investigations showed that the addition of the hybrids exhibited better dispersion and compatibility with PEN matrix than that of Fe3O4 nanoparticles. The mechanical properties and thermal stability of PEN/hybrid Fe3O4 nanocomposites had a significant improvement. Vibrating sample magnetometer (VSM) results showed that the prepared PEN nanocomposites presented soft magnetic properties. PEN nanocomposites filled with hybrid Fe3O4 nanoparticles exhibited higher saturation magnetization than that of Fe3O4 nanoparticles. The saturation magnetization (Ms) of the PEN/hybrid Fe3O4 nanocomposites increased with the increase of the hybrids and the Ms along the parallel and perpendicular direction were close to each other. These results were due to the better dispersion of the hybrids and the interfacial bonding between the hybrids and the surrounding matrix.

This study investigated the magnetism and anomalous transport properties of the melt-spun ribbon Fe2MnAl alloy. It is found that the alloy exhibits ferromagnetic order with the Curie temperature of ∼150 K, followed by another magnetic transition at TR ∼ 51 K. It is suggested there is antiferromagnetism pinning effect on the ferromagnetic matrix at the temperature below TR. A steep rise of the resistance below TR has been observed, which can be understood in terms of antiferromagnetic scattering. An appearance of the resistance maximum near the Curie temperature and the negative temperature dependence of the resistance above Curie temperature are associated with the magnetic phase transition from ferromagnetism to paramagnetism. A negative magnetoresistance at low temperature arising from inhomogeneous magnetic scattering is reported.

The processing of cross-linked polyarylene ether nitrile (PEN), which has a triazine rings structure, has been investigated under different reaction times and temperatures. In this study, the PEN films prepared by the tape-casting formed the thermally stable triazine rings by catalytic cross-linking reaction gradually, which was characterized by Fourier transform infrared spectroscopy. The chemical cross-linking reaction occurred as the CN group absorption of PEN at 2221 cm−1 decreased and a new absorption peak, at 1682 cm−1, was observed, and the absorption peak intensity would be progressively larger, with the extension of the processing time. After the formation of cross-linking networks, the cross-linking degree and thermal and mechanical properties of the processed films were improved substantially, compared with the untreated films. The film with added ZnCl2 as the catalyst was more rapidly cross-linked, and its properties were better than that without catalyst at the same treatment conditions. The glass-transition temperature (Tg) of PEN films processed at 350°C for 4 h (213.65°C) was higher than that of PEN films before the treatment (161°C), and the tensile strength was also improved significantly. The PEN was processed at 350°C for 2 h, whose initial decomposition temperature increases by about 10°C, compared with that of untreated film, at one time. The rheology behavior of the cross-linked films was processed on dynamic rheometer to monitor and track the process of polymer cross-linking reaction. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The characteristics of biomass oxygen gasification with a higher equivalence ratio (0.31–0.40) in a pilot scale (50 kg/h) downdraft fixed bed gasification system were studied using pine wood block and corn stalk briquette as feedstocks. Experiments were carried out to investigate the influence of the higher equivalence ratio on the gasification performance. The gas composition was analyzed by gas chromatography. Upon increasing the equivalence ratio from 0.31 to 0.40, the reaction temperature, gas yield, and carbon conversion efficiency increased, while the lower heating value and tar and dust contents of syngas decreased. The gas yield and carbon conversion efficiency of corn stalk briquette gasification were lower than those of pine wood block gasification by about 3.0% and 5.0% at each equivalence ratio. The higher equivalence ratio strengthened the gasification and improved the gas yield as well as carbon conversion but lowered the lower heating value of the syngas. Too high equivalence ratio (>0.40) would result in excess gasification and more combustible components being burnt out. Too low equivalence ratio (

We performed the high-pressure angle-resolved X-ray diffraction experiments on Cu3N up to 36.0 GPa. It was found that a crystal structure phase transition begins to take place at similar to 5.5 GPa on Cu3N. Under high pressure, Cu3N transforms to a new simple tetragonal structure denoted by [Cu(1)(3)Cu(2)(x)]N(1+x/3), because parts of Cu and N ions occupy the vacant sites in the crystal lattice. In this structure, Cu(1) and Cu(2) denote the primal Cu position and the vacant position in ReO3 type Cu3N, respectively. The content x is increasing with pressure, indicating that the phase transition is a gradual change. When pressure is greater than 12 GPa, x keeps 1 up to the maximum pressure, so Cu3N completely transforms to a body-center tetragonal structure, where the N sites are filled with 1/3 N ions. (C) 2010 Elsevier Ltd. All rights reserved.

Mostly read and admired as a Depression writer, John Steinbeck enjoyed a high prestige in the world for his grand theme of humanity and ingenious craftsmanship. Different from other Depression writers, Steinbeck succeeds in making people keep a refreshing faith in humanity through devastation and desolation. This paper aims at analyzing Steinbeck’s humanistic concern in Of Mice and Men, through two main aspects, the desire for land and the hunger for intimacy. In the conclusion part, it is pointed out that beyond the gloom and despair, the dream for the paradise future and the quest for genuine human relations is always the noble ideal to seek; equality, benevolence and fraternity is forever the sublime Christian spirit calling people to return, though they’re lost in their direction for the time being, to their holy native land.

Graphite nanosheets (GN) reinforced polyarylene ether nitriles (PEN) nanocomposites were successfully fabricated through masterbatch route and investigated for morphological, thermal electrical, mechanical, and rheological properties. The SEM images showed that GN were well coated by phthalonitrile prepolymer (PNP) and dispersed in the PEN matrix. Thermal degradation and heat distortion temperature of PEN/GN nanocomposites increased substantially with the increment of GN content up to 10 wt%. Electrical conductivity of the polymer was dramatically enhanced at low loading level of GN; the electrical percolation of was around 5 wt% of GN. The mechanical properties of the nanocomposites were also investigated and showed significant increase with GN loading. For 10 wt% of GN-reinforced PEN composite, the tensile strength increased by about 18%, the tensile modulus increased by about 30%, the flexural strength increased by about 25%, and the flexural modulus increased by 90%. Rheological properties of the PEN/GN nanocomposites also showed a sudden change with the GN loading content; the percolation threshold was in the range of 3–4 wt% of GN.

Large-scale production of high dielectric multiwalled carbon nanotubes using iron–phthalocyanine polymer as only carbon source at ambient pressure in nitro atmosphere under 800 °C have been reported here. The dielectric properties of the synthesized carbon tubes were measured at 2–18 GHz. Furthermore, well-ordered mesostructured carbons with graphitic framework walls were conveniently obtained by continuing heating the carbon tubes to 1000 °C, the mesoporous carbons processed high BET surface of 276 m 2 g −1 and narrow pore size dispersion. SEM, TEM, XRD and N 2 adsorption/desorption methods were employed to figure the detail structure information of materials.

A topological insulator(1-9) is a new state of quantum matter that is characterized by a finite energy gap in the bulk and gapless modes flowing along the boundaries that are robust against disorder scattering. The topological protection of the surface state could be useful for both low-power electronics(10) and error-tolerant quantum computing(11,12). For a thin slab of three-dimensional topological insulator, the boundary modes from the opposite surfaces may be coupled by quantum tunnelling, so that a small, thickness-dependent gap is opened up(13-15). Here we report such results from angle-resolved photoemission spectroscopy on Bi2Se3 films of various thicknesses grown by molecular beam epitaxy. The energy gap opening is clearly seen when the thickness is below six quintuple layers. The gapped surface states also exhibit sizeable Rashba-type spin-orbit splitting because of the substrate-induced potential difference between the two surfaces. The tunable gap and the spin-orbit coupling make these topological thin films ideal for electronic and spintronic device applications.