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A stable dibenzo-1,6,2,5-dioxadisilocine was synthesized as a difunctional electrophile for double-silylation reactions. Its molecular structure was fully characterized by spectroscopic means and single-crystal X-ray diffraction analysis. The reductive coupling with phenanthrene using a dispersion of sodium afforded an unexpected silylated polycyclic compound via a formal [3+3] dimerization of phenanthrene skeletons.A stable dibenzo-1,6,2,5-dioxadisilocine was synthesized as a difunctional electrophile for double-silylation reactions. Its molecular structure was fully characterized by spectroscopic means and single-crystal X-ray diffraction analysis. The reductive coupling with phenanthrene using a dispersion of sodium afforded an unexpected silylated polycyclic compound via a formal [3+3] dimerization of phenanthrene skeletons.

For the first time, this work presents a novel room temperature time-effective concept to manipulate the crystallization kinetics and magnetic responses of thin films grown on amorphous substrates. Conventionally, metal-induced crystallization is adopted to minimize the crystallization temperature of the upper-layer thin film. However, due to the limited surface area of the continuous metal under-layer, the degree of crystallization is insufficient and post-annealing is required. To expose a large surface area of the metal under-layer, we propose a simple and novel approach of using an Au nanodots array instead of a continuous metallic under-layer to obtain crystallization of upper-layer thin films. Spinel cobalt ferrite (CFO) thin film as a ‘model’ was deposited on an Au nano-dots array to realize this methodology. Our findings revealed that the addition of quantum-sized Au nano-dots as a metal under-layer dramatically enhanced the crystallization of the cobalt ferrite upper layer at room temperature. The appearance of major X-ray diffraction peaks with high intensity and well-defined crystallized lattice planes observed viatransmission electron microscopy confirmed the crystallization of the CFO thin film deposited at room temperature on 4 nm-sized Au nano-dots. This crystallized CFO thin film exhibits 18-fold higher coercivity (Hc= 4150 Oe) and 4-fold higher saturation magnetization (Ms= 262 emu cm−3) compared to CFO deposited without the Au under-layer. The development of this novel concept of room-temperature crystallization without the aid of additives and solvents represents a crucial breakthrough that is highly significant for exploring the green and energy-efficient synthesis of a variety of oxide and metal thin films.

Magnetization dynamics driven by an electric field could provide long-term benefits to information technologies because of its ultralow power consumption. Meanwhile, the Dzyaloshinskii-Moriya interaction in interfacially asymmetric multilayers consisting of ferromagnetic and heavy-metal layers can stabilize topological spin textures, such as chiral domain walls, skyrmions, and skyrmion bubbles. These topological spin textures can be controlled by an electric field and hold promise for building advanced spintronic devices. Here, we present an experimental and numerical study on the electric field-induced creation and directional motion of topological spin textures in magnetic multilayer films and racetracks with thickness gradient and interfacial Dzyaloshinskii-Moriya interaction at room temperature. We find that the electric field-induced directional motion of chiral domain wall is accompanied by the creation of skyrmion bubbles at certain conditions. We also demonstrate that the electric field variation can induce motion of skyrmion bubbles. Our findings may provide opportunities for developing skyrmion-based devices with ultralow power consumption.

The new sterically hindered piperidine analog, dispiro[cyclohexane-2,2′-piperidine-6′,2″-cyclohexane] (CPC(H), 2), and its N-methylated derivative CPC(Me) (3) were synthesized from commercially available starting materials in short steps. The N-lithiated amide LiCPC (4) was also isolated from 2as a cyclictrimer in single crystals and showed slightly larger steric hindrance than that of lithium 2,2,6,6-tetramethylpiperidide (LiTMP) in the competitive methylation reaction with methyl trifluoromethanesulfonate. In addition, the heterobimetallic heteroleptic zincate complexes [Li(μ-NR2)(μ-Et)Zn(Et)] (NR2= CPC, 5, and NR2= TMP, 6) were obtained as THF- and TMEDA-coordinated monomer 5·(THF)2, 6·(THF)2, 5·TMEDA, and 6·TMEDA(THF = tetrahydrofuran, TMEDA = N,N,N′,N′-tetramethylethylenediamine). These molecular structures bearing different amido ligands in single crystals showed little structural differences from crystallographic studies. Diffusion-ordered spectroscopy (DOSY) revealed that the solution structures of the zincate complexes 5·(THF)2and 6·(THF)2only differ in the number of coordination THF molecules. In the deprotonation reactions with tert-butyl 3-bromobenzoate, the zincate complexes containing the CPC ligand [Li(μ-CPC)(μ-R)Zn(R)] (R = Et (5), tBu) showed moderately improved regioselectivity for the 6 position in comparison to those containing the TMP ligand [Li(μ-TMP)(μ-R)Zn(R)] (R = Et (6), tBu).

It is popular to research promoting the light conversion efficiency of crystalline silicon solar cell photovoltaic (PV) modules. However, excellent light conversion efficiency does not mean it could maintain initial performance after long-term running. Long-term reliability of interconnection to assemble crystalline silicon solar cells in PV modules is critical to ensure that the device performs continually for up to 20 years. It is reported that most crystalline PV modules fail from corrosion and breakage of the interconnector with the solder joint. As a result, improvement of interconnection technology is highly necessary. Nickel (Ni) Micro-Plating Bonding (NMPB) is an innovative interconnection technology for crystalline silicon solar cells: copper ribbons bonded with lead or lead-free solder are replaced by copper wires bonded with Ni electroplating film. The NMPB interconnection provides key advantages: low temperature (55 °C) process, enhancement of reliability from strain and stress caused by high temperature, and coefficient of thermal expansion (CTE) mismatch between metal and silicon. Furthermore, the material of NMPB, Ni, possesses excellent corrosion resistance. High reliability was confirmed with about 1.9% degradation of output power for up to 1000 thermal cycling tests and 3.8% for 1000 h of damp heat tests in bare NMPB solar cells, while 64.7% degradation in thermal cycling tests and 23.0% in damp heat tests were confirmed in solder bonding solder cells.

The investigation of the dynamic collapse behavior of structures during strong wind disturbances provides a rational foundation for estimating the safety factor of structures. In order to discuss the essential features of dynamic collapse behavior, the analyric and numerical studies are carried out on the dynamic behavior of singledegreeoffreedom SDOF inelastic systems, also taking into consideration the effect of gravity under harmonic perturbation conditions with a mean static force. This model disturbance, which may be applied to wind disturbances, will be briefly called the harmonic excitation. The dynamic collapse condition of a system with respect to a harmonic excitation can be given by considering the elastic steadystate response of the system. If an allowable displacement of a system is specified, the harmonic excitation which induces the system to collapse can be found. Inversely, if a harmonic excitation is specified, the tolerable displacement of the system can also be found.

Polyaxial screw-rod fixation of C1-C2 is a relatively new technique to treat atlantoaxial instability, and there have been few reports in the literature outlining all possible complications. The purpose of this case report is to present the occurrence and management of occipital bone erosion induced by the protruded rostral part of a posterior atlantoaxial screw-rod construct causing headache.

The fabrication of magnetic oxide nanodots was studied without the use of conventional lithographic techniques and patterning masks. Self-assembled Au nanoparticles with an average size of approximately 17 nm were formed via simple sputtering and used as the underlayer for the magnetic oxide film. Subsequently, hexagonal ferrite, SrFe12O19, was sputtered on the Au nanoparticles, resulting in an SrFe12O19/Au sample. Self-assembled SrFe12O19nanodots were obtained with an average size of 40–50 nm. The morphology of the Au nanoparticle underlayer acted as a template for the SrFe12O19film, such that the self-assembled SrFe12O19nanodots were formed. In addition, the fabrication of the SrFe12O19film on the Au nanoparticles induced the down-sizing of the magnetic domain structures of SrFe12O19to the nanoscale. Importantly, although the nanodots showed nanometric magnetic domains, a sufficient magnetization magnitude in the SrFe12O19nanodots was revealed. Furthermore, the SrFe12O19nanodot fabrication area was ~8.5 cm2, thereby the current technique can be applied to the development of future functional magnetic nanodots.

The tensile property and hydrogen embrittlement (HE) behavior in the submicrocrystalline ultra-low carbon steel produced by HPT straining were investigated. Elongated grains with 300 nm thickness and 600 nm length with high dislocation density were formed by the HPT straining at a rotation-speed of 0.2 rpm under a compression pressure of 5 GPa. The engineering tensile strength of the HPT processed ultra-low carbon steel for > 5 turns was 1.9 GPa, which is similar to the value of maraging high-alloy steels. The elongation increased with strain (at 5 to 10 turns), is caused by the reduction of the stress concentration due to the existence of continuously recrystallized grains. HE occurred in the HPT processed specimen for 5 turns with high tensile strength of 1.9 GPa under hydrogen atmosphere. However, its HE was suppressed via recovery process by annealing at low temperature while maintaining the high strength.

In order to fabricate thick SmCo5 film, the dependences of the magnetic properties of SmCo/Ru/Cu/Ru films and its multilayer films on the SmCo layer thickness were studied. The SmCo/Ru/Cu/Ru film with the SmCo layer thickness up to 200 nm showed the perpendicular magnetic anisotropy while the multilayer film with the total SmCo layer thickness of 1000 nm indicated the magnetic easy axis was in the perpendicular direction. It was found that the multilayered structure is preferable for the increase in total thickness of the SmCo layer with the perpendicular anisotropy. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The alloying effects of Pd on the hydrogen solubility and the resistance to hydrogen embrittlement are investigated for Nb-xmol%Pd-ymol%Zr (x=0~19; y=0, 1) alloys. The hydrogen solubility at 673 K is found to decrease with increasing Pd content in the alloys. Both pure Nb and Nb-Pd alloys possessed ductility in vacuum at 673 K. However, severe hydrogen embrittlement occurs in pure Nb when it is tested under the hydrogen pressure even as low as 0.01 MPa. In view of the small punch (SP) absorption energy, the addition of Pd into Nb improves the resistance to hydrogen embrittlement by decreasing the hydrogen solubility in the alloy, although brittle fracture is still observed in the Nb-15mol%Pd alloy tested under a hydrogen pressure of 0.015 MPa at 673 K.

BaFe12–x(Mn0.5Co0.5Ti)x /2O19 hexaferrites with x = 1, 2 and 3 were prepared by a sol–gel process. The reaction temperature was much lower than that of the conventional ceramic method. The ferrite powders possess a hexagonal shape and are well separated from one another. Thermogravimetric analysis, X-ray diffraction, a scanning electron microscope, an ac susceptometer and a vibrating sample magnetometer were used to analyze their structures and magnetic properties. The results showed that for all the samples magnetoplumbite structures have been formed. The samples with x = 2 and 3 have higher magnetic susceptibility and larger coercive force. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The development and characterization of hexagonal ferrite powders of BaFe9Mn1.5Ti1.5O19, BaFe9Mn1.5Co1.5O19, and BaFe9Ti1.5Co1.5O19 as the microwave absorbers have been investigated. The ferrites were fabricated by conventional ceramic technology. The developed ferrite powders 80% by weight were mixed with polyvinylchloride plasticizer and fired to form rubber-ferrite with the thickness of 1.5 mm, 2 mm and 2.5 mm. XRD was used to identify structures of the samples. The magnetoplumbite structures for all the samples have been formed. Vibrating sample magnetometer was used to determine the hysteresis loops of barium ferrite and BaFe9Mn1.5Ti1.5O19 at room temperature. The vector network analyzers in the frequency range of 12 to 20 GHz have measured the reflection loss properties of rubber-ferrite. It was concluded that BaFe9Mn1.5Ti1.5O19 with thickness of 2 mm could be designed as a wide-band microwave absorber. By SEM, the size and morphology of grains in BaFe9Mn1.5Ti1.5O19 ferrite were examined. The results showed that ferrite with grain size of 5 µm do not have any impurities. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The microstructure and magnetic properties of L10 ordered Fe55Pt45 and (Fe55Pt45)1–x–(Al2O3)x thin films fabricated by in situ ordering process were studied. For Fe55Pt45 thin films, preheating substrate above 250 °C induces a transformation from a disordered fcc structure to ordered L10 phase and the films become magnetically hard. The addition of Al2O3 made fcc-fct transformation temperature rise from 250 °C to 400 °C and the average grain size of thin films reduce from 20 nm to 6nm or less. The reason why the fcc-fct phase transformation starts at lower substrate temperature can be well understood by the discussion of relationship between phase transformation and kinetic energy of sputtered atoms. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

NdFeB thin films of good perpendicular magnetic anisotropy have been successfully deposited on W underlayer by DC magnetron sputtering. Cu and Al elements are introduced to improve the structural and magnetic properties of the NdFeB films. The deposition temperature is lowered to 400 °C by the addition of 1.0 at.% Cu. The average grain size is reduced to 10 nm by the introduction of 10.0 at.% Al. With the reduction of the grain size, the exchange coupling interaction between the grains is weakened. The magnetization reversal process of the grains directly depends on the grain size and shape. Before Al addition, most of the grains are demagnetized by magnetization incoherent rotation but in the film doped with 5.0 at.% Al, the magnetization is coherently reversed, as demonstrated by the comparison of the physical grain volume and the thermal switching volume. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

NdFeB thin films were synthesized by a dc magnetron sputtering system. The influence of composition and temperature of crystallization on the microstructure and magnetic properties of NdFeB thin films was investigated. It was found that excessive Nd and B addition was helpful in promoting granular structure and reducing grain growth as well as in modifying magnetic properties. The excess elements were precipitated and well distributed around the shells of hard magnetic grains. This actively decreased the intergranular interactions between hard grains. Films made on heated substrate were also compared to those fabricated by post annealing. The former method was proved to be very effective to produce hard NdFeB thin films with good perpendicular anisotropy on a W underlayer, whereas films made by the latter process were isotropic. The maximum coercivity was obtained near 10 kOe in films annealed at 600 °C. The intergranular interactions were characterized by δM plots. It was found that annealed samples have a much stronger exchange coupling interaction than do the in situ deposited samples. Therefore, the magnetization reversal process in annealed films is mainly controlled by domain wall motion while it is more likely to be dominated by incoherent magnetization reverse in in situ deposited thin films, defined by the dependence of coercivity Hc(θ) on the measuring angle θ. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The magnetic and structural properties of FePt and FePt–Al2O3 films deposited by rf-sputtering on 7059 corning glass substrates were investigated. The coercivities of the films can be adjusted from 20 to 12.3 kOe through controlling the ordering degree of the FePt phase. With the increasing annealing temperature TA from 100 to 650 °C, the average grain size of FePt grains increased from about 10 to 50 nm in the FePt films, while it kept almost a constant of about 10 nm in the alumina-added films. The measurements of the deviation Δm*(H) as a measure for particle–particle interaction and SFD (switching field distribution) revealed that the addition of alumina contributed to diluting the intergranular exchange coupling interaction. In the case of the FePt–Al2O3 (25 vol%) films with varying film thickness from 20 to 180 nm annealed at 550 °C for one hour, no obvious changes in structural and magnetic properties due to the variation of film thickness was detected. Grain size was in the vicinity of 10 nm, squareness S about 0.9, coercivity squareness S* almost a constant of about 0.85, and the in-plane coercivities kept high value of about 5.5 kOe.

Ba ferrite thin films were successfully prepared by using a facing target sputtering system. Magnetic, crystallized thin films were obtained both by ex-situ and in-situ processes. In this paper, thin films prepared by these two processes were studied on the aspects of crystal structure, magnetic properties and surface morphology. The mechanism of magnetization reversal of thin films prepared by both processes was discussed. It is found that the imperfection in the thin films strongly effects the magnetic properties of these films.

The investigation of the dynamic collapse behavior of structures during strong wind disturbances provides a rational foundation for estimating the safety factor of structures. In order to discuss the essential features of dynamic collapse behavior, the analyric and numerical studies are carried out on the dynamic behavior of single‐degree‐of‐freedom (SDOF) inelastic systems, also taking into consideration the effect of gravity under harmonic perturbation conditions with a mean static force. This model disturbance, which may be applied to wind disturbances, will be briefly called the harmonic excitation. The dynamic collapse condition of a system with respect to a harmonic excitation can be given by considering the elastic steady‐state response of the system. If an allowable displacement of a system is specified, the harmonic excitation which induces the system to collapse can be found. Inversely, if a harmonic excitation is specified, the tolerable displacement of the system can also be found.

The structural phase transition of a ferroelectric liquid crystal has been studied by energy-dispersive X-ray diffraction. In the nematic phase, the spatial and temporal behaviour of the molecular orientation is observed by applying an external magnetic and/or electric field to the specimen. The orientational convection of the nematic alignment is studied by analyzing the intensity fluctuation of the diffracted peaks by Fourier transformation.

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•An 11-year-old pubertal girl presented with complaints of the acute onset of a severe headache and sudden deterioration in her right eye vision for the last 2 days.•The present patient is the 22ndand the youngest patient with clinical pituitary apoplexy since the advent of the CT scan.•The literature was reviewed to focus on the incidence and characteristics of clinical pituitary apoplexy in children and adolescent patients.

Ba-ferrite films with small c-axis dispersion angle Δθ50are suitable for ultrahigh density recording media. The dependences of partial oxygen gas pressure PO2and total discharge gas pressure PTotalon the characteristics of Ba-ferrite films were clarified. It was found that there were three regions, where films were composed of single layer of spinel type ferrite(PO2≤0.002mTorr), mixed layer of spinel and magnetoplumbite type ferrites (0.003 \leq P_{O2} \leq 0.2mTorr) and single layer of magnetoplumbite type ferrite (PO2>0.3 mTorr). In the range of P02between 0.005 and 0.2 mTorr, spinel-like ferrite layer plays very important role as an underlayer to decrease the Δθ50of the Ba-ferrite layer. Films deposited at relatively low PO2and PTotalexhibit very smooth surface and Δθ50as small as2.5\sim3.5\deg.

This paper presents a numerical study of reduced beam section (RBS) beams with vertical and horizontal stiffeners. For RBS beams, it is speculated that strength deterioration will be caused by lateral buckling and local buckling. Supplemental lateral bracing (SLB) can prevent lateral buckling but not prevent local buckling in the RBS portion. In the previous research, the effect of vertical or horizontal stiffeners in RBS portion was shown to restrain local buckling of the RBS portion. But RBS with vertical stiffeners causes stress concentration at flange, and strength of RBS with horizontal stiffeners is lower than RBS with vertical stiffeners. In this paper, various patterns of placing stiffeners at the RBS portion are presented. The effect of vertical stiffeners and horizontal stiffeners arranged at the RBS portion is discussed based on length. It is confirmed that, without placing supplemental lateral bracing (SLB), vertical and horizontal stiffeners can delay the occurrence of local buckling and prevent stress concentration. Moreover, the strength can be sustained above 0.8Mp.