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The homogeneous anisotropic hardening (HAH) model was implemented into a finite element (FE) code in order to predict springback for an advanced high strength steel (AHSS) sheet sample after double-stage U-draw bending. The finite difference method (FDM) was utilized as an alternative way to calculate the derivatives of this advanced distortional plasticity model allowing the update of the equivalent plastic strain and stress tensor at each time step in the user-material subroutines (UMAT and VUMAT). The FDM makes it easier to derive the stress gradient of complex yield surfaces. The proposed FDM-based stress update algorithm was verified by comparing the springback profiles after the single- and double-stage U-draw bending tests for a DP980 sheet sample predicted with analytical and numerical approaches. In addition, the springback measurement parameters and computational efficiencies depending on both approaches were also compared. The results indicate that the computational efficiency and accuracy of the FE simulations with the FDM-based stress update algorithm were similar to those of the analytical method.

This study investigates the use of refined potato protein (RPP) obtained from the potato ( Solanum tuberosum ) tubers of “Gogu valley” for their antimicrobial properties and its effects on growth performance, apparent nutrient digestibility and microbial populations in feces and large intestine of weanling pigs. Pigs ( n = 280; Landrace × Yorkshire × Duroc; average initial body weight of 5.96 ± 0.66 kg; 23 ± 3 d of age) were allotted on the basis of their body weight and sex to five dietary treatments (each treatment comprised of 4 replicate pens with 14 pigs in each) in a randomized complete block design. The dietary treatments were: PC (positive control; basal diet + 150 ppm apramycin sulfate and 10 ppm colistin sulfate), and RPP (basal diet added with 0, 200, 400 and 600 ppm RPP). The RPP showed in vitro antimicrobial activity and at the concentration of 150 ppm inhibited the growth of tested microbes ( Staphylococcus aureus , Salmonella choleraesuis , Salmonella gallinarum and Escherichia coli ). Pigs fed with antibiotic diet showed better growth performance and had lower populations of total bacteria, coliforms and Staphylococcus spp. in the feces and large intestine when compared with pigs fed RPP diets. Increasing the levels of RPP in diets linearly improved performance and reduced the populations of total bacteria, coliforms and Staphylococcus spp. in feces and contents of colon and rectum. The apparent fecal digestibility of DM, CP and apparent ileal digestibility of amino acids did not differ among pigs fed antibiotic and RPP diets. These results suggest that antibiotics were more effective in improving the performance of pigs, while feeding of RPP also improved the performance and reduced the harmful microbes being more effective at higher levels. Thus at higher levels RPP obtained from the potato tubers of Gogu valley can be a potential replacement of antibiotics in the feed of weanling pigs.

To investigate the effects of metabolizable energy and lysine restriction on performance, and gene expression of leptin and myostatin, three hundred twenty day-old Ross broiler chicks were randomly allotted to four treatments. Birds were subjected to their respective diets comprising two levels of ME (3200; 2880 kcal kg-1) and two levels of lysine (1.10; 0.88%) during days 8 to 21. The dietary crude protein levels were reduced with the proportion to the lysine levels, while ratios of essential amino acids relative to lysine were similar for all diets. During restriction, weight gain, breast muscle and abdominal fat yield were lower in birds fed lysine-restricted diets. Relative myostatin mRNA abundance was increased in breast muscle of lysine-restricted birds, while expression of leptin mRNA in abdominal fat was downregulated by energy and lysine restriction. During realimentation, birds previously fed with energy and/or lysine-restricted diets had comparable performance as birds fed unrestricted diets. At day 42, energy and lysine restriction increased relative myostatin mRNA expression in breast muscle and birds previously fed diet restricted in both energy and lysine had the highest relative myostatin mRNA expression (energy × lysine interaction, P < 0.001). The relative leptin mRNA abundance was significantly lower in birds previously fed energy-restricted diets. These results indicated that early energy and lysine restriction from day 8 to 21 exhibited growth compensation during realimentation. In addition, myostatin and leptin mRNA expression in breast muscle and abdominal fat were modulated by nutritional treatments and were closely associated with changes in breast muscle yield and abdominal fat deposition. Key words: Metabolizable energy, lysine, myostatin, leptin, broiler

This study was conducted to investigate the effects of dietary fat inclusion to create two energy levels on reproductive performance, milk compositions and blood profiles in lactating sows. Twenty-four multiparous sows were randomly assigned to four treatments according to a 2×2 factorial arrangement. Two energy levels (3365 and 3265 kcal/kg) were created by supplementing different fat levels (high and low). Higher energy level resulted in less (P

The effects of lysine restriction during grower phase and realimentation during finisher phase on growth performance, nutrient digestibility, blood metabolites, carcass traits and pork quality were studied. Sixty-four pigs (two castrated males and two females per pen) weighing 34.34±5.22 kg were assigned to four dietary treatments. During grower (35–55 kg), pigs were fed isoenergetic lysine-restricted diets. The different lysine content of diets were 0.950 (NRC recommendation), 0.760, 0.665 and 0.570%, corresponding to lysine restriction of 20, 30 and 40%. Then all pigs were fed with common finisher 1 (55–85 kg) and 2 (85–115 kg) diets. Lysine restriction during the grower phase resulted in poor performance and lower concentration of blood metabolites but improved the nutrient digestibility and efficiency of lysine utilization. Compensatory growth response in terms of improved weight gain and feed efficiency was observed in pigs previously fed lysine-restricted diets during finisher 1, but the co...

A total of 280 weanling pigs (Landrace × Yorkshire × Duroc) at an average initial body weight of 7.2 ± 0.88 kg were used in a 28-day growth study to investigate the effect of potato protein (PP) on growth performance, digestibility, small intestinal morphology and microbial populations in feces and large intestine. Pigs were randomly allotted on the basis of their body weight and sex to five dietary treatments in a randomized complete block design. There were four replicate pens per treatment and each pen comprised of 14 pigs. The dietary treatments were: PC (positive control; basal diet + 1.5 g apramycin sulfate/kg and 1.0 g colistin sulfate/kg) and PP (basal diet supplemented with 0.00, 2.50, 5.00 and 7.50 g PP/kg diet. The PP was extracted from a special breed of potato ( Solanum tuberosum L. cv. Golden valley) and had minimum inhibitory concentration of 1000–1250 μg/ml against Staphylococcus aureus , Salmonella spp. and E. coli . Pigs offered PC diets exhibited significantly faster (P Staphylococcus spp. (days 21 and 28) in the faeces was lower (P Staphylococcus spp. in caecum and rectum. The dietary treatments had no effect on the morphology of the small intestine. These results suggest that antibiotics elicit better performance by reducing pathogenic bacteria and that potato protein obtained from Golden valley had antimicrobial properties since it (PP) effectively reduced the pathogenic bacteria in feces and large intestine and hence may be an alternative to medicated feed with antibiotics.

Alumina-deficient (Al2O3/SiO2 = 1.12, molar ratio), orthorhombic mullite whiskers with a diameter of 0.6–1.8 μm (aspect ratio >30) have been manufactured by firing compacts of coal fly ash and NH4Al(SO4)2·12H2O powders, with a small addition of NaH2PO4·2H2O, at 1300 °C for 10 h. The manufacturing process, the morphology, and structure of the whiskers are described.

Freeze casting is a useful forming technique to produce complex-shaped ceramic parts. The colloidal processing stage is an essential step for preparation of freeze casting slurries. In order to optimize freeze casting slurries, several processing additives, such as dispersant, binder, surfactant, and cryo-protectant are usually employed. Dispersion and suspension rheology of aqueous alumina/ zirconia slurries with 55 and 60 vol.% solid loading have been characterized in terms of the effect of organic additives, and the resulting microstructures of the freeze cast green and sintered materials examined.

Because the parasitic load on most polymer electrolyte fuel cell systems is dominated by pressure losses across the flow fields, understanding the flow channel dynamics has garnered significant recent attention. The current work is aimed at enabling advanced design of reactant flow channels by elucidating the details of the velocity fields within various reactant flow channel geometries. Gas-phase measurement is critical to ensuring that the results are valid for real fuel cell systems, and for application of this technique to the study of flow channels with two-phase obstruction phenomena. In the current research, gas-phase velocity fields have been measured using particle image velocimetry (PIV) in representative geometries, including a straight channel (for technique validation) and a 180° switchback with channel-to-land ratio of 1:1. The accuracy of the measurement depends on the ability of the seed particles to follow the flow. Numerical simulations have been performed to develop a criterion for identifying appropriate seed particles. The research presented is a first step toward measuring velocity fields in novel flow reactant channels in operational cells.

In order to improve the mechanical properties of pure mullite ceramics, a process has been developed that incorporates Zr(Y)O 2 into mullite by infiltrating partially reaction sintered (porous) mullite compacts with mixed ZrOCl 2 ·8H 2 O and YCl 3 ·6H 2 O solutions, corresponding to ZrO 2 /Y 2 O 3 = 97/3 (mol.%). The infiltration of small amount (∼7.2 wt.%) of Zr(Y)O 2 significantly improved the densification behavior and mechanical properties of mullite bodies sintered at 1620 °C, for 10 h. The mocrostructure contained a few elongated mullite crystals (aspect ratio > 6) which were embedded in a fine-grained matrix. The relatively large Zr(Y)O 2 inclusions were mainly dispersed intergranularly in the matrix, but small ( 2 O 3 content than that of stoichiometric mullite composition formed at triple points of the mullite/mullite grains.

To characterize the nano-oxide layer (NOL) in specular spin valve multilayer, naturally oxidized CoFe layer was inserted between pinned CoFe layers. The under-, optimum, and over-oxidized samples were obtained by control of the oxidation time and the oxygen flow rate. The NOL was analyzed to be Fe oxide mainly by X-ray photoelectron spectroscopy (XPS) data. As oxidation increased, the content of Fe oxide and the thickness of the NOL increased and too much thicker NOL was obtained in case of over-oxidation. We concluded that the lower magnetoresistance (MR) ratio and the more slanted magnetization curve than the optimum could be attributed to the Fe oxide as a non-ferromagnetic defect or magnetic discontinuity in case of under-oxidation and the too thick NOL in case of over-oxidation.

Si/Ta/Ni–Fe/Mn–Ir/Co–Fe/NOL/Co–Fe/Cu/Co–Fe/Ta bottom specular spin valves were prepared by dc magnetron sputtering method. Under optimal oxidation conditions, the magnetoresistance ratio (MR ratio) and the Hex (exchange bias field) increased from 7.8% and 247 Oe without nano oxide layer (NOL) to 10.3% and 320 Oe with NOL, respectively. And the Hin (interlayer coupling field) decreased from 35 to 19 Oe. These results indicate that NOL in the Co–Fe pinned layer improves the magnetic and electrical properties of spin valve. The NOL is formed discontinuously and this thickness range is about 0.5–2 nm. The chemical analysis shows that Fe-oxide is formed preferentially in the NOL.

Si/Ta/Ni–Fe/Mn–Ir/Co–Fe/NOL/Co–Fe/Cu/Co–Fe/Cu/capping bottom specular spin valves were prepared by using the DC magnetron sputtering method. We studied the effect of capping layers on the magnetic and thermal properties of specular spin valves. We can obtain a high magneto resistance ratio, high exchange bias field, and low interlayer coupling field by using Ta and Al capping layers. The thermal aging experiment showed that the Ta capping layer was more stable than the Al capping layer. We can obtain low interlayer coupling filed about 1 kA/m by using Al 2 O 3 oxide capping layer.

As a conductive layer, sputter-deposited Al–Cu 1 at.% thin film was investigated, with particular focus on the effect of Cu precipitates and film strain on the electric conductivity. The 400-nm-thick film was deposited on Si wafer and heat-treated at 200 and 480 °C. Cu precipitation was investigated using electron microscopy and film strain using XRD. As a result of heat treatment, changes in the electric resistivity showed the same trend as the film strain. This study concluded that the trends in resistivity and film stress could be related to Cu precipitation to some extent. In other words, the resistivity changes depending on whether the precipitates are coherent with the Al matrix and on the distribution of the precipitates.

Cross-geometrical Cr/Co/Al-Ox/Co/Ni-Fe tunnel junctions were fabricated by magnetron sputtering. To form an insulating layer, The Al layer was oxidized in an atmosphere of oxygen-argon mixture at low power after deposition. To enhance the coercivity of the bottom Co layer, The Cr seed layer was deposited on the glass and it led to increase in coercivity. The coercivity increase is due to the increase of roughness through the Cr thickness. In over oxidation time, the oxidation of Co bottom layer and flat interface of insulator can increase the bottom Co coercivity. But TMR ratio gradually decrease. TMR ratio is relevant with Cr thickness, insulator thickness, and oxidation time. The maximum TMR ratio was 14% at room temperature and the TMR ratio was decreased to half at 0.51 V.

An investigation was conducted to examine the effects of diamond-like carbon (DLC) overcoats on the wear durability of the VCR head and the signal dropout caused by wear debris while the VCR is in operation. Approximately 40-nm-thick DLC films were deposited directly on the Mn-Zn ferrite head pole by an electron cyclotron resonance (ECR) system using CH/sub 4/ source gas. The deposition temperature was maintained at below 100/spl deg/C to prevent deterioration of the epoxy resin attached to the head. From the experiment we were able to discover that DLC films accumulated successively from the bottom of the grooves on the head surface smoothing out the surface. In general, DLC heads outperformed the bare heads. The head life is increased significantly by the wear durability of DLC films and the continuous supply of lubricating DLC films. We were also able to discover that leftover DLC films along the head edge provide continuous lubricity on the rubbing head surface during use. Furthermore, most of the wear debris was more readily expelled from the DLC head surface than from the bare head. Therefore, the onset time of the signal dropouts was found to be delayed six times in DLC heads in the still frame mode.

In giant magnetoresistance (MR) spin valve (SV), the thin nano-oxide layer (NOL) has been used for the confinement of conduction electrons, which contributes to spin scattering in film and its interfaces. In this article, we have investigated the effects of NOLs, which were fabricated by a plasma oxidation of Co–Fe layer on the magnetic properties and MR in a Mn–Ir–Pt-based SV. The NOLs were located at the middle of pinned layers and between a free and a metal-capping layer. The adjusted NOL could result in high MR and strong exchange coupling field (Hex). From a high-resolution electron microscopy analysis, the oxide was formed at about 1 nm. For SVs employing an oxide-capping layer, the strong reflectivity at the interface of a free and an oxide-capping layer should lead to the large decrease of an interlayer coupling field, which could possibly improve Hex.

Introduction Various techniques have been described deceased donor liver transplantation (DDLT) procurement. One is a technique whereby almost total dissection is done in the porta hepatis and perihepatic detachment is carried out before cross-clamping the donor aorta. In another approach, after the donor aorta is cross-clamped, rapid and minimal en bloc dissection is performed with minimal manipulation. We evaluated early posttransplant graft function among liver procurement techniques. Method Between January 2008 and August 2012, we performed 45 consecutive adult DDLTs. One patient was excluded from this analysis due to early death from sepsis after transplantation. The 44 included patients were divided into two cohorts according to the procurement technique: A warm dissection ( n = 23; 52%) and a cold dissection group ( n = 21; 48%). We compared early posttransplant graft function using the aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (T-bil), and prothrombin time (PT) values of the two groups from the first to seventh postoperative day. Result The AST values in the warm group were significantly greater than those in the cold group on postoperative days 3 and 5. In addition, the ALT values in the warm group were greater than those in the cold group on postoperative days 4, 5, and 6. Moreover, the T-bil values in the warm group were greater than those in the cold group on postoperative days 2, 3, 4, 5, 6, and 7. However, there were no differences in PT values. Conclusion During liver procurement for DDLT, rapid en bloc procurement with minimal manipulation after clamping the donor aorta achieved better early graft function posttransplantation.

We have investigated the annealing effect of magnetic tunnel junctions (MTJs) with or without nano-oxide layer (NOL). For MTJ without NOL, TMR ratio increased up to 300 °C and the highest value was 21.6%. On the other hand, TMR ratio of MTJ with NOL increased up to 400 °C and the highest value was 22.7%. As shown in the auger electron spectroscopy (AES) and transmission electron microscopy (TEM) results, this improved thermal stability is due to NOL in the pinned layer. Mn diffusion into Al–O barrier is blocked and interface of Al–O is smothered by NOL. These may be the main reasons of high thermal stability of MTJ with NOL.

We have investigated the annealing effect on the magnetic tunnel junctions (MTJs) having different oxygen content. In All MTJs, enhanced tunneling magnetoresistance ratio could be obtained at the optimum temperature of each MTJ. From the results, it is closely related with the oxygen content in the oxide layer. The variation of an effective barrier width (S) was also critically depended on the oxidation state in MTJs. MTJ oxidized for 40 s was not fully oxidized and showed the slight increase of effective S due to the reaction with an unreacted Al during annealing. However, the further oxidized MTJ showed the decrease of the effective S, and the extent of which was different with oxygen content in oxide layer.

Synthetic top and bottom spin valves including the Mn–Ir–Pt/Co–Fe (P1)/Ru/Co—Fe (P2) synthetic pinned layer were prepared by controlling the thickness difference (Δ t =P1–P2) of Co–Fe layers. The effective exchange field ( H eff,ex ) and giant magnetoresistance (GMR) properties of both synthetic type SVs were investigated as a function of Δ t . The H eff,ex was dependent largely on the Δ t . The GMR properties are strongly dependent on the stacking sequence of synthetic SVs and Δ t . Based on the magnetic and electrical properties at room temperature, the thermal stability of synthetic SVs was also evaluated at various elevated temperatures in both types of SVs.

Early intervention and maintenance treatment for schizophrenia patients may prolong the duration of exposure to antipsychotic agents; however, there have been few studies on the neurotoxicity of these agents. Here, we investigated the effects of antipsychotics on cell viability and autophagy in rat primary neurons. Cultured cortical neurons obtained from rat embryos were treated with various concentrations of haloperidol and clozapine, and the neuronal toxicity was assessed by measuring lactate dehydrogenase (LDH) activity and 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. Autophagosomes were quantitated by measuring the level of microtubule-associated protein 1A/1B-light chain 3 (LC3-II) by Western blot and immunofluorescence staining. Autophagic flux was assayed using bafilomycin A1 and GFP-mCherry-LC3 transfection. Haloperidol and clozapine decreased the viability of neurons in vitro in a concentration- and time-dependent manner. We also observed increased accumulation of autophagosomes after antipsychotic treatment. Using bafilomycin A1 and GFP-mCherry-LC3 transfection, we discovered that haloperidol and clozapine inhibited autophagosome turnover resulting in a dysfunctional autophagic process, including impaired lysosomal fusion. Together, these results suggest that haloperidol and clozapine negatively affect neuronal viability, possibly by blocking autophagolysosome formation.

1. A total of 320-d-old Ross broilers were used in a 6-week study to investigate the effects of feeding lower energy and protein diets from d 8 to 14 on growth performance, blood profiles, and gene expression of leptin and myostatin. 2. Broilers were randomly allotted to 4 treatments, each treatment applied to 4 pens with 20 birds in each. During first week, all the birds were fed on a common starter diet (13.4 MJ ME/kg, 230 g/kg CP and 11.0 g/kg lysine). The birds were then subjected to their respective treatment diets from d 8 to 14. Treatment diets comprised two ME levels, 13.4 and 12.0 MJ/kg, each with two levels of CP, 230 and 184 g/kg. This was followed by feeding common starter and finisher diets for the last 4 weeks. 3. Dietary protein reduction resulted in poor performance and feed efficiency while energy reduction resulted in poor feed efficiency between d 8 and 14. From d 14 to 42 birds previously fed diets lower in energy and protein showed similar body weight gain and feed intake to well-fed birds. Moreover from d 8 to 14, birds fed on energy and protein-reduced diets had lower nutrient metabolisability coefficients. 4. The blood urea nitrogen (BUN) and relative weights of heart and breast muscle were lower in birds fed protein-reduced diets while energy reduction resulted in lower plasma glucose, abdominal fat and intestinal weight at d 14. At d 42, birds fed on the protein-reduced diets had lower BUN, breast muscle weight and small intestine length, while feeding on the energy-reduced diets resulted in lower abdominal fat. 5. Upregulated myostatin mRNA expression in breast muscle and downregulation of leptin mRNA expression in abdominal fat were observed in birds fed on protein and energy-reduced diets, respectively. 6. In conclusion, early nutrient reduction affected growth performance and produced lesser abdominal fat in broilers. Moreover, early energy and/or protein reduction could change muscle and fat metabolism by regulating the expressions of myostatin and leptin.

Modern genotype primiparous and multiparous sows (Yorkshire x Landrace, n=48) were used to evaluate effects of dietary lysine intake during late gestation and lactation, and their interaction on reproductive performance. Sows were randomly allotted to two gestation lysine (G, 0.6% or 0.8% lysine) treatments based on parity in a 2 x 2 factorial arrangement, and each treatment had 12 replicates comprising 1 sow. Then all the sows were assigned to two lactation lysine (L, 1.0% or 1.3% lysine) treatments within parity and gestation treatments in a 2 x 2 x 2 factorial design, and each treatment comprised six replicates with 1 sow/replicate during lactation. Feeding higher lysine level during gestation increased sow body weight and backfat thickness (P=0.001) and body condition was better (P=0.001) in multiparous than that of primiparous sows. Both of the lysine levels during lactation and parity influenced sow body condition and reproductive performance (P

This paper presents the centrifugation using the self-rotating secondary flow in the microchamber. The feasibility of the microfluidic centrifuge was demonstrated numerically an experimentally. The centrifugation of the nano-particles was visualized and its performance was characterized quantitatively. Also, a new finding of the transient motion of the rotating flow influenced the stable operation of the centrifuge.

Summary form only given. We have demonstrated a hybrid Er-doped fibre amplifier (EDFA) with a flat gain over a dynamic gain range of 9 dB, with a minimum of optical components and without any electronic gain control. The wide dynamic range is a result of an increase of the gain level in the phosphosilicate EDF following a decrease in the backward-propagating ASE when the input signal power increase, even though the overall EDFA gain decreases.

This paper describes a loss-coupled 1.55 /spl mu/m DFB laser with an automatically buried absorptive InAsP layer. The use of the automatically buried InAsP layer implemented by a single step growth makes the device fabrication process much easier than that of conventional loss-coupled DFB LDs. The fabricated DFB LDs with AR/HR(3%/95%) coated facet show a low threshold current of 9 mA (26 mA) and a slope efficiency as high as 0.41 mW/mA (0.34 mW/mA) at 25/spl deg/C (85/spl deg/C), respectively, and a SMSR as high as 50 dB, a high single mode yield as high as 93%, and high reliability.

Summary form only given, as follows. Summary form only given. As an application for spin-valve type giant magnetoresistance (GMR) devices, exchange biased NiFe/NiO bilayers have been studied extensively. The current study focuses on the formation of a second phase at the NiO layer and resultant change of the exchange anisotropy in the bilayers. The NiFe/NiO bilayers were deposited on silicon wafers by sputtering and a Ta capping was applied on the bilayer. Target materials were Ni/sub 81/Fe/sub 19/ alloy and NiO oxide. Ar pressure effects on the magnetic properties of the NiO film were studied under constant conditions of input power and film thickness. Rutherford backscattering spectroscopy (RBS) and X-ray photoelectron spectroscopy (XPS) were used to investigate the composition and the chemical state of the NiO film. The magnetic properties of NiO changed with Ar pressure. The exchange bias field (Hex) shows a maximum at 1 mTorr Ar pressure and the coercivity at 2.5 mTorr. The antiferromagnetism of NiO was destroyed gradually with increasing Ar pressure This destruction of antiferromagnetism occurs mainly at the interface of NiO and NiFe, due to the formation of an amorphous phase. RBS results show that there are two Ni oxide phases, antiferromagnetic NiO and nonmagnetic Ni/sub 2/O/sub 3/. We conclude that the amorphous Ni/sub 2/O/sub 3/ phase results in the destruction of exchange anisotropy of NiFe/NiO bilayers.

Summary form only given. High output signal and easy controlling of bias point are necessary to achieve 100 G/bit/sup 2/ magnetic areal density in magnetic recording technology. Specular spin valve in which the NOL enhance specular electron scattering and smooth interface were suggested as a new technology. In this paper, we studied effect of nano-oxide layer (NOL) formation at the interface between ferromagnetic layers and investigated chemical bonding of NOL. Si/Ta(5nm)/NiFe(3.5 nm)/Mn-Ir(6 nm)/CoFe(2 nm)/NOL/CoFe(2 nm)/Cu(2.5 nm)/Co-Fe(t nm)/Ta(2.5 nm) specular bottom spin valves were deposited on Si(100) substrate by auto-process magnetron sputtering. The base pressure was less than 3x 10/sup -8/ Torr. The samples were deposited under 5 mTorr. A NOL was formed in the load lock chamber by exposing to pure oxygen gas. Samples were annealed for 30 min at 200/spl deg/C under 3 kOe in-plane magnetic field in a vacuum furnace (1 x 10/sup -5/ Torr), followed by cooling to room temperature for 2 hour. The magnetoresistance (MR) and the exchange bias field (H..) increased from 7.8 and 247 without NOL to 10.2 % and 320 Oe with NOL, at t =40 nm, respectively Also the coupling field (H/sub f/) and sheet resistance (R/sub s/) decreased from 35 and 4.9 without NOL to 19 Oe and 4.67 Q/sq with NOL, respectively. In case of using NOL the decreased sheet resistance indicates that the probability of spin dependent scattering of conduction electrons is increased because electrons have long mean free path in the ferromagnetic layers. Improved magnetic properties of spin valve by inserted NOL are considered to be due to the specular effect. The values of rms, peak-to-valley and average roughness decreased from 1.46, 45.3 and 0.92 to 1.32, 15.5 and 0.81 nm, after O/sub 2/ exposure This indicates that the interface greatly smoother by NOL formation. This uniform interface reduce ferromagnetic static coupling between two ferromagnetic layers XPS results showed that NOL was constituted from about 31 % Fe/sub 2/O/sub 3/ and about 51 % FeO. And Co-oxide was negligible. TEM will be presented in more detail microstructure of specular spin valve.

The authors propose an all-digital code tracking scheme for a bandlimited cellular direct-sequence code-division-multiple-access (DS-CDMA) system, which uses bandlimited Nyquist chip pulse shaping and orthogonal coding. The code tracking loop has a decision-directed noncoherent structure to handle the orthogonally coded DS-CDMA signals. The performance of the tracking loop is derived analytically. >

Summary form only given.Broadband gain-flattened optical amplifiers are essential for increasing the capacity of wavelength division multiplexed transmission systems. Among the several approaches to flatten the gain of an amplifier, gain flattening filters (GFFs) based on long period gratings (LPGs) are strong candidates because of the ease of fabrication, the flexibility in spectral-shaping, and very low back reflection. There are, however, two major problems that had to be overcome to use the LPGs as a GFF: temperature sensitivity and polarization dependency. UV-induced birefringence in hydrogen loaded fibers makes fiber gratings sensitive to the polarization of the incident light. In this paper, we characterize the birefringence in LPGs by the measurements of polarization dependent loss and demonstrate a fiber-twist method for reducing the birefringence LPGs.

We have investigated the effect of nano oxide layers (NOLs), which were fabricated by a plasma oxidation of CoFe layer on the magnetic properties and magneto-resistance (MR) in a Mn–Ir–Pt based spin valve. The adjusted NOL could result in the high MR and the strong exchange coupling field ( H ex ). From a high resolution electron microscopy analysis the oxide was about 1 nm. The strong reflectivity at the interface of a free and oxide capping layer should lead to the decrease of an interlayer coupling field, which could possibly improve the H ex .

We studied the thermal properties of specular and conventional spin valves. The specular spin valve showed better thermal properties (e.g. slow MR degradation and sheet resistance increment) than those of conventional spin valve. It is considered that the Mn–Co–Fe–O is formed in the NOL at 543–578 K and this acts as a diffusion barrier for Mn during high-temperature annealing process.