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Unexpected tracheal narrowing was observed in a patient with Duchenne muscular dystrophy during a corrective operation for thoracolumbar scoliosis. As the operating time progressed, peak airway pressure and end-tidal CO2 increased gradually in the prone position. We found a floppy portion of the trachea using fiberoptic bronchoscopy (FB) in the prone position. We advanced a wire-reinforced tube toward the carina beyond the lesion. This allowed correction of the ventilatory abnormalities. We encountered another patient scheduled for the same operation. We performed FB in advance before the position change and observed a narrowed portion of trachea. We advanced the tracheal tube under FB beyond the pathologic portion and then moved the patient into the prone position. The operation was done successfully without any problems.

Background: The aim of this study was to compare the streamlined liner of the pharynx airway (SLIPA) with the classic laryngeal mask airway when used by novice personnel. Methods: There were 114 patients enrolled into this study who underwent general anesthesia were randomly allocated into one of 2 groups; LMA group (n = 57) or SLIPA group (n = 57). After insertion, insertion success rate, insertion time, and hemodynamic responses to insertion were accessed. After surgery, postoperative airway morbidity (sore throat, dysphonia, dysphagia) were evaluated. Results: The SLIPA was successfully inserted in 96% of patients (55/57) and the LMA in 93% (53/57) (P = 0.408). First attempt success rates were 88% (44/57) and 77% (50/57) in the SLIPA and the LMA (P = 0.142). The successful insertion time in SLIPA group (33.4 ± 11.0 sec) was significantly shorter than that of LMA group (38.8 ± 16.6 sec) (P = 0.048) and the insertion time at the first attempt was also shorter in SLIPA group (31.0 ± 6.3 sec) than LMA group (34.7 ± 8.6 sec) (P = 0.013). There was no statistically significant difference between the two groups in hemodynamic responses and postoperative airway morbidity. Conclusions: The SLIPA was similar to the LMA in insertion success rate, hemodynamic response, and postoperative airway morbidity by novice personnel. The insertion time at the first attempt and successful insertion time of the SLIPA were significantly shorter than those of the LMA. Therefore, the SLIPA could be a useful alternative to the LMA as primary SGA for novice personnel. (Korean J Anesthesiol 2012; 63: 136-141)

Solutions containing the components Au(+), dpae (dpae is 1,2 bis-(diphenylarsino)ethane), and X(-) (X is Cl, Br, or I) can produce two different types of crystals with the composition Au(2)(μ-dpae)X(2): colorless blocks and colorless needles. Crystallographic studies of these crystals show that they are polymorphs with different structural motifs. In the α-polymorphs, which are isostructural, individual molecules of Au(2)(μ-dpae)X(2) form discrete dimers through two identical Au···Au contacts. In the β-polymorphs, which each have unique crystallographic parameters, the Au(2)(μ-dpae)X(2) molecules assemble into polymeric chains through aurophilic interactions. The Au···Au contacts in the α-polymorph (3.1163(2), 3.1064(3), and 3.0842(2) Å for Cl, Br, I, respectively) are somewhat shorter than those in the β-polymorph (3.1668(3), 3.1042(8), and 3.1046(2) for Cl, Br, I respectively). The systematic study we now report shows an increase in the strength of this aurophilic interaction for the α-form in the series X = ClBrI, which is in good agreement with theoretical studies by Pyykkö and his co-workers.

The change in the residual stress and its effect on mechanical bending and magnetic properties of sputtered amorphous Sm–Fe–B thin films are investigated as a function of annealing temperature. Two stress components of intrinsic compressive stress and tensile stress due to the difference of the thermal expansion coefficients between the substrate and thin film are used to explain the stress state in as-deposited thin films, and the annealing temperature dependence of residual stress, mechanical bending and magnetic properties.

The free layer switching characteristics in magnetic tunnel junctions with the structure NiFe/AlO x /Co ( y nm)/Ru/Co (7– y nm)/FeMn/NiFe are investigated as functions of the relative Co layer thickness and the cell size by computer simulation. The bias field varies linearly with y , and the relative Co layer thickness dependence of the bias field is greater at smaller cell dimensions. At y =4, the bias field of the free layer remains nearly unchanged with the cell size, due to the balance of the stray field contribution from neighboring layers. The contribution from the lower permalloy layer (next to the FeMn) is found to be not small. The calculated hysteresis loops are in qualitative agreement with the experimental results.

An attempt is made to achieve a very high density recording on continuous longitudinal media with a newly designed planar-type write head, which can generate a very high write field up to about 14 kOe. A particular emphasis is given to the writability of the planar-type head on the medium with a very high value of magneto-crystalline anisotropy ( K ). A reasonably good bit pattern with a density of 605 kfci is generated on the medium with K =4.5×10 5 J/m 3 . However, bit shape is rather curved, and the track width of the written pattern is significantly higher than the head track width. These problems are relieved with the use of a trimmed planar head showing narrow field distribution.

Both analytical and numerical calculations are carried out to examine the relative strength of the interlayer dipole fields in comparison to that of the interlayer exchange coupling in nanostructured cells of synthetic ferrimagnets as functions of their size, shape, and thickness. The relative strength in aligning the magnetizations antiparallel increases with decreasing cell size and with increasing cell thickness, in agreement with the size and thickness dependence of the magnetostatic interactions. As the cell shape changes from rectangle to ellipse, the relative strength decreases, due to the decreased density of free poles with the shape change. The relative strength of the interlayer dipole field is found to be not small, being approximately 10% of the strongest interlayer exchange coupling observed for the CoFeB/Ru/CoFeB structure. In an elliptical cell with the dimensions of 160 nm (long axis) x 80 nm (short axis) x 2 nm (thickness), for example, the strength is 0.016 erg/cm2.

The magnetization switching window of nanostructured synthetic ferrimagnets with lateral dimension of 160 nm x 80 nm under combined in-plane magnetic fields along the longitudinal and transverse directions is investigated by numerical calculation using an analytical equation for the total energy. The considered total energy equation precisely accounts for the magnetostatic energy, which is significantly large in nanostructured magnetic cells. Due to the complex magnetization alignment of synthetic ferrimagnets, a different switching criterion based on the reversibility of magnetization process is used, instead of the simple criterion frequently used for single magnetic layers. Synthetic ferrimagnets with various thickness asymmetries are considered, and switching windows are calculated both in static and dynamic conditions. The static switching windows show a smaller dependence on the thickness asymmetry than the dynamic switching windows do. The dynamic switching window at a large thickness asymmetry resembles that of a single magnetic layer. The results are discussed in terms of energy profiles that can be obtained by locating the lowest energy path linking the two stable states from the total energy surface.

The temperature increase due to Joule heating in a nanopillar of a magnetic tunnel junction sandwiched by top and bottom electrodes was calculated by the finite element method. The results for the critical condition for the current-induced magnetization switching measured over a wide current-pulse range were taken from the literature. At long pulse widths, the temperature increase was solely dependent on the magnitude of the critical current density. However, no saturation in the temperature increase occurred for short pulse widths. In this case, the temperature increase additionally depended on the pulse width, so that a broad maximum occurred in the pulse width (or the critical current density) dependence of the temperature increase. The original results for the critical condition were corrected by accounting for the temperature increase and these corrected results, together with the Slonczewski equation, were used to extract an accurate value for the thermal stability factor.

A new plasma process, i.e., combination of PIII&D(Plasma Immersion Ion Implantation and Deposition) and HiPIMS(HIgh Power Impulse Magnetron Sputtering), was developed to implant non-gaseous ions into materials surface. The new process has great advantage that thin film deposition and non-gaseous ion implantation can be achieved in a single plasma chamber. In this process, Al ions were successfully implanted into glass, and Ge thin films of ∼100 nm thickness were deposited on to Al-implanted glass by HiPIMS process. After annealing at ∼400 °C, crystallized Ge thin film could be attained with very low residual Al content.

A 41-year-old woman, who had no thrombotic risk factors and past history except congenital scoliosis, underwent central venous catheterization (CVC) before correction of the scoliosis. When internal jugular vein (IJV) catheterization using the anatomical landmark technique failed, CVC under ultrasound guidance was tried. As a consequence, thrombosis and hypoplasia of the right IJV were incidentally detected by ultrasonography. Central venous catheters were then successfully placed in other veins under ultrasound guidance. Also, after examinations to rule out the possibility of pulmonary embolism and to clarify the causes of the IJV thrombosis, the patient was found to have protein S deficiency. CVC under ultrasound guidance should be recommended to prevent the failure of cannulation and complications such as thromboembolism in patients who could possibly have anomalies of vessels as a result of anatomical deformities caused by severe scoliosis, even if patients do not have thrombotic risk factors such as a history of central catheter insertion or intravenous drug abuse, cancer, advanced age, cerebral infarction, and left ventricular dysfunction. Also, if venous thrombosis is found in patients without predisposing risk factors, one should ascertain the cause of the hypercoagulable state, for example protein S deficiency, and perform appropriate treatment and prevention of venous thromboembolism.

We investigate the magnetic properties of nanocrystalline Fe73.5Cu1M3Si13.5B9 (M=Nb or Mo) alloys when C is substituted for B up to 2 at%. It is found that the permeability and coercivity deteriorate with the content of C in the case of both M=Nb and Mo. The saturation magnetization also deteriorates as C is substituted for B in the case of M=Mo but it improves linearly with the C content in the case of M=Nb. This increase in the saturation magnetization of the Fe-Cu-Nb-Si-B alloy with C addition can provide an opportunity to overcome one of the main disadvantages, low magnetic flux density, of the alloy. In the latter part of the work we also investigate the magnetic properties of Fe76.5−yCu1Nby (Si0.5B0.4C0.1)22.5 (0≤y≤3) alloys, particular emphasis being given to the role of Nb in the presence of C. It is found that C may help Nb to suppress the growth of α-Fe grains in the alloy.

The magnetic properties of an Fe73.5Cu1Nb3Si13.5B9 alloy with nanoscale crystalline structure have been investigated as a function of the melt temperature. In the temperature range of 1240 to 1380 °C investigated in the present study, the permeability increases with the melt temperature. This result may be explained in terms of the reduction in the magnetic anisotropy as a function of the melt temperature. This is supported by the results for the remanence ratio, which also increases with melt temperature in a similar manner to the permeability. In the latter part of the work described in this paper, the relationships between the permeability and the coercivity, and the permeability and the remanence ratio have been investigated for the nanocrystalline alloy. It was found that the permeability is correlated more closely to the remanence ratio than the coercivity.

The spontaneous Hall effect in amorphous Tb–Fe and Sm–Fe thin films, which possess excellent magnetic softness, is investigated to seek a possibility of practical applications of these thin films. The resistivity of Tb–Fe thin films ranges from 180 to 250 μΩ cm as the Tb content varies from 35 to 46 at. %. Tb–Fe thin films show negative Hall resistivity ranging from −7.3 to −5.0 μΩ cm in the same composition range, giving the normalized resistivity ratio from −4.1% to −2.0%. On the other hand, the resistivity of Sm–Fe thin films ranges from 150 to 166 μΩ cm as the Sm content varies from 22 to 31 at. %. Sm–Fe thin films show positive Hall resistivity which varies from 7.1 to 2.8 μΩ cm in the same composition range, giving the normalized resistivity ratio from 4.8% to 1.7%. Between the two different sets of samples, Tb–Fe thin films with perpendicular anisotropy are considered to be more suitable for practical applications, since saturation is reached at a low magnetic field.

We report the salient features of the magnetization behavior of melt-spun ribbons of (Dy 0.33 Fe 0.67 ) 1− x B x with x =0, 0.05, 0.1 and 0.15 alloys. The temperature dependence of magnetization and low-temperature hysteresis loops were measured using a vibrating sample magnetometer during heating from 5 to 900 K, with an applied field of 50 kOe. Our results show that the addition of B seems to decrease the magnetic order and hence to decrease the exchange stiffness and the Curie temperature. Very large values of the coercive force at a low temperature of 5 K, ranging from 19 800 to 22 900 Oe, was observed. The rapid increase of the coercive force at low temperatures is explained by the topological disorder due to the presence of rare earth spins distributed randomly.

This prospective study was conducted to evaluate the feasibility of two-lung (TL) ventilation with low tidal volume anaesthesia compared with one-lung (OL) ventilation for needlescopic bleb resection. Patients with spontaneous pneumothorax that underwent bleb resection with a 2-mm thoracoscope were enrolled. During the operation, the tidal volume was set at 4.0 mL·kg⁻¹ in the TL group and 8.0 mL·kg⁻¹ in the OL group; the respiration rate was set at 23 and 12 breaths·min⁻¹, respectively, at the same inspiratory oxygen fraction (50%). A total of 108 patients (55 patients in the TL group and 53 in the OL group) were included in this study. Airway pressure was significantly lower in the TL group (mean ± sd 8.0 ± 3.3 versus 24.0 ± 3.9 mmHg in the OL group; p

Results are reported from a Monte Carlo study of the vacancy formation energy and the configurational vacancy formation entropy in monatomic crystals and in intermetallic compounds as a function of vacancy concentration. Simulations have been carried out for both square and bcc lattices. Although the results have been obtained for the case in which the lattice energy is determined by nearest-neighbour central pairwise interactions only, the results are of more general interest. Contrary to calculations based on the Bragg-Williams approximation, a very significant configurational contribution to the excess vacancy formation entropy may exist at vacancy concentrations often encountered in intermetallic compounds. The vacancy formation energy, often assumed constant in analytical treatments, may also change quite significantly with vacancy concentration.

Results are reported from Monte Carlo simulations of non-stoichiometric compounds with the B 2 structure and which contain a high concentration of vacancies. The model chosen is a rigid lattice with nearest-neighbour atom interactions only. The vacancy concentrations evaluated correspond with two-phase equilibrium and not those obtained by minimising the single phase free energy. The partial thermodynamic properties of the components are evaluated along the phase equilibrium boundary together with the concentrations of defects on the two sub-lattices. The triple-defect assumption, frequently used in analytical treatments for vacancies in these compounds, is shown to be of very limited value.

The magnetic properties of a set of Tb x Fe 1− x magnetostrictive thin films are measured under applied stress in a cantilever configuration. The 1 μm thick films are produced on 200 μm thick Si (1 0 0) substrates by magnetron sputtering in Ar atmosphere. Magnetic characterization is obtained with complementary fluxmetric and magneto-optic Kerr effect methods. The role of stress-induced anisotropy is discussed, with reference to the intrinsic anisotropy which can lie in-plane or out-of-plane depending on composition. An optimal film composition at x =54 at% is determined for sensor applications requiring magnetic softness and stress sensitivity.

Induced anisotropy with a large energy of 6×104 J/m3 is formed in an amorphous Sm–Fe based thin film by sputtering under an applied magnetic field of 500–600 Oe. The induced anisotropy results in a large anisotropy in magnetostriction, a strain anisotropy ratio reaching as high as 35, although intrinsic magnetostriction is affected only slightly. The large strain anisotropy allows one to realize a large strain in a particular direction and, hence, it is of significant practical importance. Induced anisotropy is also found to be formed by postannealing under applied magnetic field, but the magnitude of anisotropy energy formed is very small.

An analysis and equivalent circuit model for an H-shape cross slotted aperture-coupled microstrip patch antenna (ACMPA) are presented. The study in the paper helps us to understand better the antenna property and also provides an easy way to design the antenna. The ACMPA consists of three conductor layers such as patch, ground plane, and feed line. The coupling exists in two places. One between the patch and a slot in the ground and the other between the slot and the feed line are represented by the ideal transformers. To calculate the turn ratio of the ideal transformer effectively the reciprocity theorem and the spectral-domain immittance approach are used. Moreover, vertical slots of ‘H’ slot are considered as the reactive loads. The H-shape cross-slotted ACMPA operating at 3GHz and 5GHz simultaneously is fabricated. The good agreement between theoretical and measured results is shown.

Effects of Sm on the magnetic and magnetostrictive properties of Tb–Fe thin films are investigated. Four alloy systems, RxFe100−x (R=Tb+Sm) with x=39.8, 41.9, 43.7, and 45.8, are examined with Sm content varied from 0 (Sm free) to 2.2 at. %. In-plane anisotropy is found to be enhanced by the addition of Sm and the strongest in-plane anisotropy occurs in the Sm content range of 1 to 2 at. % depending on R content. At low magnetic fields of 1000 Oe and below, magnetostriction increases significantly with increasing Sm content, and reaches a maximum at an intermediate Sm content where well-developed in-plane anisotropy is observed. At higher magnetic fields of 3000–5000 Oe, however, no substantial improvement of magnetostriction occurs with the addition of Sm. The Sm content dependences of magnetization and coercive force are also examined.

We measure the high frequency magnetic properties of polymer-bonded Terfenol-D rods compacted from powders of different size, in order to analyze the effect of structure and preparation conditions in sonic or ultrasonic frequency applications. Magnetic characterization at high fields and in the kilohertz range is made using a custom built amorphous metal yoke. Experimental data are analyzed using the theory of losses and the dynamic Preisach model. The electrical resistivity is estimated to be about 1.25 μΩ m, higher than in grain-oriented materials. The classical contribution to dynamic power loss, directly proportional to conductivity, is found to be dominant. The analysis establishes a direct connection between static and dynamic magnetic properties and structural characteristics, such as the density, conductivity, and the powder size, which can be modified for optimization purposes.

Permalloy (Ni81Fe19) thin films are etched by ion beam etching (IBE) or reactive ion etching (RIE), and the variation of magnetic properties with etching time is investigated. Magnetic softness of permalloy thin films deteriorates as etching proceeds, i.e., film thickness decreases. Coercivity begins to increase steeply at a thickness of 0.4 μm and reaches 16 Oe for IBE and 8 Oe for RIE at 0.09 μm. Effective magnetization is increased by 0.2 kG with IBE but decreased by 0.7 kG with RIE. From an atomic force microscopy analysis and independent wet etching experiments, the increase of coercivity is proved to be attributed to the increase of surface roughness as a result of etching. Etching-induced defects are also responsible for the increase of coercivity, which is confirmed by a measurement of electrical resistivity and x-ray diffraction analysis. Ion beam etching process appears to affect magnetic properties to a greater extent than reactive ion etching process.

Permalloy thin films deposited by rf magnetron sputtering are ion beam etched or reactive ion etched. Effects of the dry etching on magnetic properties are examined by ferromagnetic resonance and the results are shown as a function of film thickness (etching time). The perpendicular resonance field shifts toward a higher field as ion beam etching proceeds, but it moves to a lower field in the case of reactive ion etching. The effective magnetization of ion beam etched thin films is slightly increased, but the opposite behavior is observed in reactive ion etched thin films. The exchange stiffness constant decreases gradually with ion beam etching whereas a sudden drop to about 5/spl times/10/sup -7/ erg/cm occurs by reactive ion etching. This result can be explained by a surface etching-damaged layer.

The TE scattering characteristics of the mushroom-type EBG structures in parallel plate waveguide was studied using Fourier transform and mode-matching techniques. The theoretical model was expressed in a fast convergent series. This model is useful for the analysis and design of mushroom-type EBG structures to reduce EMI problems.

Background We performed thoracoscopic surgery for pneumothorax using two-lung ventilation with low tidal volume and evaluated the feasibility and safety of this procedure. Methods Forty-six patients (mean age, 23.6 ± 10.47 years) each with a primary spontaneous pneumothorax underwent wedge resection with chemical and mechanical pleurodesis. Two-lung ventilation anesthesia was performed with a single-lumen endotracheal tube, and the tidal volume was reduced to 4 mL/kg; the respiratory rate was increased to 24 cycles/min. Airway pressure, end-tidal CO 2 , and the results of blood gas analysis were obtained right after endotracheal intubation and during the operation, and were compared. Results The tidal volume was 496.2 ± 94.33 mL at anesthesia induction, which decreased to 243.9 ± 34.43 mL during the two-lung ventilation. In 5 patients, the tidal volume was additionally decreased by 32.5 ± 12.58 mL ( p = 0.014) to obtain an optimal working field. The differences between the airway pressure, pH, partial pressure of carbon dioxide, and partial pressure of oxygen were significant between the two measurement times. However, all of the values of the arterial blood gas analysis were within normal range. The oxygen saturation (99.9% ± 0.69% versus 99.8 ± 0.72%; p = 0.160) and end-tidal CO 2 (33.2 ± 3.74 mm Hg versus 34.1 ± 4.19 mm Hg; p = 0.157) were not significantly different. The time from intubation before the incision was 17.1 ± 4.18 minutes, the operation time was 31.9 ± 14.48 minutes, and the total anesthesia time was 65.8 ± 15.02 minutes. Conclusions Thoracoscopic surgery for primary spontaneous pneumothorax using two-lung ventilation with low tidal volume was technically feasible.

In this paper, a tunable notch resonator based on CSRRs using varactor is proposed. This new resonator, called by the authors as varactor-loaded complementary SRRs (VLCSRRs), is a promising component thanks to its compact and tunable characteristic as VLSRRs.

In this paper, the UHF RFID tag antenna which has a SRR as a radiating part and inductively coupled feeding method are analyzed and designed. By using a SRR, the antenna size can be reduced and using an inductively coupled feeding method, we can obtain a wide bandwidth and a simple matching technique to directly attach to a tag chip. Also equivalent circuit model of the tag antenna is presented and unknown variables are analyzed and checked. Therefore the tag antenna can be designed for various tag chips and frequency ranges.

The relations between the thermodynamic properties of the unary lattice gas and the equivalent binary substitutional and interstitial alloys are discussed. New methods for the estimation of the partial particle energy in a lattice gas from Monte Carlo simulations in both the petit and grand canonical ensembles are presented and evaluated. Taken together with well established procedures for estimating the particle chemical potential and more recent procedures for estimating the lattice gas pressure, it becomes possible, for the first time, to obtain reliable determinations of both the partial and integral quantities for internal energy, entropy and free energy at a given temperature and composition in a rigid binary alloy from the one Monte Carlo experiment in either ensemble. Some illustrative results are given for the square lattice with nearest neighbour interactions.

A new method for the rapid, direct evaluation of the component chemical potentials in substitutional solid solutions from a single Monte Carlo simulation is described. The method is carried out by using the removal or addition of a test-site. The reliability of the test-site method is evaluated for binary solutions on a square lattice with first and second nearest-neighbour interactions and on the b.c.c. lattice with nearest-neighbour interactions. The results obtained are compared with those from the exact solution (for the equi-atomic composition on the square lattice) and with those obtainable from Monte Carlo simulations by less direct routes. Both above and below the critical temperature the new method is found to be highly satisfactory. The new method has a distinct advantage over previous methods in being equally applicable to the calculation of component chemical potentials in multi-component solutions.

A new method for the evaluation of the lattice-gas pressure from Monte Carlo simulations is proposed and is illustrated for a square lattice with nearest-neighbour interactions. The method involves the determination of the derivative of the partition function with respect to the change in the total number of sites by using the removal or addition of a test site. Estimates of the lattice gas pressure by this test-site approach are compared with those obtained from the exact solution (for the half-filled lattice), the thermodynamic integration method, and the method of Meirovitch which involves the calculation of the pressure from the integral entropy. Both above and below the critical temperature the new method is found to work very well. It has the advantage of speed over the other methods and is, therefore, the most suitable for use in phase equilibrium calculations.

Results are presented for some coherent and incoherent phase diagrams for ternary systems, which have been obtained by Monte Carlo simulations. An appropriate computer algorithm, which permits the chemical potentials of the particles and the lattice gas pressure of the equivalent binary lattice gas in two separate phases to be equalised, is described. A comparison is made with phase diagrams for the same systems but obtained by using the point, pair and tetrahedron cluster variation approximations. It is found that, for the same values of the interaction energy and temperature used, the phase diagrams obtained by using the Monte Carlo method are significantly different from those obtained by using the point and pair cluster variation approximations. The phase diagram obtained by using the tetrahedron cluster variation approximation, however, is found to be only slightly different from that obtained in the present work.

Monte Carlo results for the partial thermodynamic properties and the long-range order parameter of ordered CsCl-type intermetallic compounds are presented and are compared with those obtained from the zeroth (Bragg-Williams) approximation. The model chosen is a rigid bcc lattice with nearest-neighbour central pairwise interactions. The simulations have been carried out at two reduced temperatures, T T c = 0.9 and 0.7143 . The results for all the partial thermodynamic properties obtained from the two-sublattice model in the zeroth approximation are found to agree well with those obtained from the Monte Carlo simulations at compositions close to stoichiometry. Further away from stoichiometry, however, the results for the partial energy and entropy differ significantly, although these differences approximately compensate, making the results for the partial free energy agree quite well over a wide composition range. It is also found that the position of the second order phase transition boundary can be determined reliably from the strong singularity in the partial energy as an alternative to obtaining its position from the weak singularity in the chemical potential.

A novel compact microstrip bandstop filter using spiral resonators (SRs) is proposed. An array of SRs topology which is etched on the center line has stopband characteristics. And this microstrip bandstop filter can be implemented with very small size because of the sub-wavelength effect of SRs. The 3-cell SR filter is fabricated and verified by measurements. We have obtained low insertion loss in the passband and high rejection level in the stopband with steep cutoff. This novel structure is easy to fabricate and is a promising structure that is compatible with MMIC or PCB process.

In stacks using a Ru/Ta composite spacer [Pt/Co]6/Ru/Ta/CoFeB/MgO, both strong interlayer exchange coupling and perpendicular magnetic anisotropy are achieved. The composite spacer has the additional advantages of high post-annealing stability over a conventional Ru spacer; for a Ru (0.8 nm)/Ta (0.4 nm) spacer, where the antiparallel coupling is strongest, the coupling strength remains nearly constant at the highest annealing temperature of 375 °C. An interlayer exchange coupling is observed at very small Ru thicknesses down to 0.2 nm, which can be compared with the previous limit of 0.6 nm.

Considering the nonlinear model of active magnetic bearings, a new means of nonlinear control is presented which treats variables as rotating vectors in the control plane, specially the unbalance. It becomes easy to cancel out the effect of this perturbation in a rotating reference. Therefore, the rotor can rotate around any desired point, particularly the geometric center or the center of gravity. Simulations illustrate the efficacy of this control law.

Magnetic properties of giant magnetostrictive Sm–Fe and Sm–Fe–B thin films are systematically investigated over a wide composition range from 14.1 to 71.7 at. % Sm. The amount of B added ranges from 0.3 to 0.8 at. %. The microstructure mainly consists of an amorphous phase in the intermediate Sm content range from 20 to 45 at. %. Together with an amorphous phase, crystalline phases of Fe and Sm also exist at low and high ends of the Sm content, respectively. Well-developed in-plane anisotropy is formed over the whole composition range, except for the low Sm content below 15 at. % and the high Sm content above 55 at. %. As the Sm content increases, the saturation magnetization decreases linearly and the coercive force tends to increase, with the exception of the low Sm content where very large magnitudes of the saturation magnetization and the coercive force are observed due to the existence of the crystalline α-Fe phase. The coercive force is affected rather substantially by the B addition, resulting in l...

A commercial program package based on finite element method (COMSOL) is used to calculate magnetic field intensity resulting from the free poles formed at the magnetic cell edges. The magnetic cell stack and dimensions are relevant to high density magnetic random access memory applications. The calculated field intensity is found to be large, indicating the importance of considering magnetostatic interactions in device applications.

Experimental results on the current induced magnetization switching of nano-patterned IrMn/CoFe/Cu/CoFe spin-valves are reported. The main emphasis is the increase of MR and the reduction of the critical current density through an improved fabrication process. A method using a batch-fabricated trilayer template is developed with the junction features defined by a platinum(Pt) stencil mask. Nano-pillars with the lateral dimensions (150times80 nm2) are fabricated by electron-beam lithography, including a wet etching to form a nanotemplate. A key to the improved fabrication process is the formation of the recessed part of the SiO2 layer which helps to reduce the shadow effect during the deposition of the spin valve multilayers into the nanotemplate. Both the MR ratio and the critical current density are enhanced by the new improved fabrication process. The observed critical current density is 5.98times106 A/cm2, which is significantly smaller than the value of 1.16times108 A/cm2 observed in a similar device fabricated using a conventional fabrication process.

A detailed characterization and analysis of the microwave properties of a set of nanogranular (Fe0.7Co0.3)71B22Ni7 films under an applied magnetic dc field ranging from 0 to 45 kA/m is presented. A full microwave characterization of the films is performed up to 20 GHz using a vector network analyzer (VNA) connected to a matched microstripline or coplanar waveguide, loaded with the films. The evolution of the FMR frequencies and line-widths is derived as a function of the field applied along the easy axis (in-plane) and discussed with reference to the film nanostructure and the combination of anisotropy, demagnetizing and applied fields.

Experimental results concerning the scalar piezomagnetic coefficients of Co-based ferrites at room temperature are presented and discussed. To increase the mechanical properties, the ferrite powders are bonded by a phenol-based matrix. The Young's modulus of the samples is about 8 GPa. The permeability of the samples μ z σ ( H ) and the slope of magnetostriction curve d 33 σ ( H ) at constant stress, which are the most important piezomagnetic coefficients for stress sensing and mechanical actuation, are discussed in detail with respect to sample density changes due to different content of binder and compaction pressure.

The magnetostriction of melt-spun ribbons of the alloys (R/sub 0.33/Fe/sub 0.67/)/sub 1-x/B/sub x/ (R=Tb/sub 0.3/Dy/sub 0.7/ and 0/spl les/x/spl les/0.06) is investigated as a function of wheel speed during melt-quenching. The low field sensitivity of magnetostriction with magnetic field is found to be good for the alloys with x/spl les/0.04 over a wide range of wheel speed. This magnetostrictive behavior is in contrast with that observed previously for Dy-Fe and Tb-Fe based alloys and is thought to be due to low intrinsic magnetocrystalline anisotropy of the compound.

The magnetostriction of TbFe and TbFeB thin films is systematically investigated over a wide composition range from 40.2 to 68.1 at.% Tb for the B-free alloys and from 44.1 to 66.8 at.% Tb for the B containing thin films. The films were fabricated by rf magnetron sputtering. The microstructure mainly consists of an amorphous phase at low Tb contents and, at high Tb contents, a mixture of an amorphous phase and an /spl alpha/ Tb phase. Excellent magnetostrictive characteristics, particularly at low magnetic fields, are achieved in both TbFe and TbFeB thin films; for example, a magnetostriction of 138 ppm is obtained in a TbFeB thin film at a magnetic field as low as 30 Oe. These excellent magnetostrictive properties of the present thin films are supported by the excellent magnetic softness, the coercivity below 10 Oe and a typical squared-loop shape with the saturation field as low as 1 kOe. It is considered that, due to the excellent low field magnetostrictive characteristics, the present TbFe based magnetostrictive thin films are suitable for Si based microdevices.

DNA damage, lipid peroxidation and protein oxidation were evaluated in rats exposed to a 1% isoflurane atmosphere with or without alcohol administration (administrated by gastric intubation at 4 g/kg body weight as a 50% solution). Single cell gel electrophoresis assays were performed in order to evaluate DNA damage occurring in the lymphocytes, spleen, bone marrow, brain, livers and lung of rats exposed to 1% isoflurane for 30 or 60 min with/without ethanol. Levels of malondialdehydes (MDA), a metabolite of lipid peroxidation, were determined in plasma and tissues. Carbonyl contents were also analyzed to determine levels of protein oxidation in plasma and tissues. Levels of DNA damage in lymphocytes, bone marrow, and the organ tissues of rats exposed to isoflurane were found to increase time dependently, and alcohol increased DNA damage. Lipid peroxidation and protein oxidation results showed patterns that differed from those of DNA damage. Levels of MDA in plasma, bone marrow, spleen, and the livers of rats exposed to isoflurane with/without ethanol were found to be time dependently increased, but this was not observed in the brain or lung. However, protein oxidation levels were significantly increased in the plasma, brains, and lungs of rats exposed to isoflurane, and exposure to isoflurane and alcohol, significantly increased these levels in plasma and brain. The present study demonstrates that isoflurane exposure results in significant DNA damage in rat lymphocytes, bone marrow, spleen, brain, livers, and lung. Moreover, alcohol was found to be as a strong inducer of DNA damage, lipid peroxidation and protein oxidation. However, no evidence in association between DNA damage, lipid peroxidation and protein oxidation was found. Regarding the effects of isoflurane and alcohol on oxidative damages, single strand DNA damages may be a useful biomarkers and blood cells and plasma appear to be more sensitive targets to oxidative damage than other tissues.