Effects of N-methacryloyl amino acid applications on hybrid layer formation at the interface of intertubular dentin

To understand the role of NMAA in the bonding of composite resin to a dentin surface, we investigated the effects of N-methacryloyl amino acid (NMAA) application on the expansion of aggregated collagen fibers, formation of a hybrid layer, and the tensile bond strength between composite resin and dentin. Four NMAA derivatives--N-methacryloyl-alpha-glycine (NMGly), N-methacryloyl-gamma-amino n-butyric acid (NMBu), N-methacryloyl-alpha-hydroxyproline (NMHPro), and N-methacryloyl-alpha-glutamic acid (NMGlu)--were prepared and applied to dentin surfaces which had been etched with 40% by mass H3PO4 and air-blown. The shrunken collagenous layer expanded by approximately 50% to 70% by volume of the original collagenous layer thickness after application of the NMAA primers. Application of the bonding agent and composite resin after NMAA treatment resulted in the formation of a hybrid layer. The thickness of the hybrid layer was somewhat smaller than the collagenous layer formed by the NMAA treatment only, regardless of the type of NMAA used. The thickness of the hybrid layer was approximately ten times larger than that formed without NMAA treatment. Although all NMAA primers formed hybrid layers of similar thickness, higher tensile bond strengths, from 13 to 15 MPa, were obtained when etched and air-blown dentin was treated with NMBu, NMGly, or NMGlu. NMHPro gave only 6.6 MPa, a value similar to that obtained when no NMAA was used. We concluded, therefore, that formation of the hybrid layer is a necessary but insufficient condition for high bond strength.     

Contact and interconnect formation on compound semiconductor devices by ionized-cluster beam deposition

A new deposition technology, namely the ionized-cluster beam deposition method, was applied to form contacts and interconnects on III–V compound semiconductor devices. Au alloy films deposited by this technology had strong enough adhesion to an insulator layer to be a satisfactory interconnection. A step approximately 8 μm high at an angle of 90° to the semiconductor was covered fully with an Au alloy film obtained by this method. Electrical ohmic contacts for p-type GaP and GaAs were successfully obtained at substrate temperatures of 400 °C and 300 °C respectively without any further annealing process; this resulted in better device characteristics because of the lower process temperatures and also made the device less expensive because of a reduction in fabrication time.     

Analysis of four change detection algorithms in bi-temporal space with a case study

Although change detection algorithms for temporal remote sensing images have been compared using various datasets, there is no general agreement on their performance for separating change and no-change. This study compared image differencing, image ratioing, image regression, and principal component analysis (PCA) from a mathematical perspective. Error analysis showed that no-change pixels with errors are expected to be located within an error zone in bi-temporal space. Bi-temporal space consists of two temporal axes of target pixel values observed successively. All algorithms confine a no-change area to a zone delineating change and no-change pixels in the space. Image ratioing defines a fan-like sector as a no-change area, generally unsuitable for change detection. The other algorithms confine a no-change area to a strip-like zone. Image differencing defines a no-change zone with a fixed slope, leading to its inability to specify flexibly the error zone that varies with different conditions. In the examined case, image regression and standardized PCA (SPCA) achieved the best performance for change detection, followed by PCA, image differencing, and image ratioing.     

A comparative numerical study of hybrid-stabilized argon–water electric arc

The paper presents numerical simulations of the discharge and the near-outlet regions of the hybrid-stabilized argon–water electric arc. Two different numerical methods for solving the set of conservative equations for the continuity, momentum and energy have been applied. The major difference between the results using the two methods occurs in the temperature distribution in arc fringes within the discharge chamber. This fact influences the potential drop, overpressure, reabsorption of radiation and arc efficiency. It is shown that the radial profiles of temperature at the exit nozzle are less influenced by different temperature distribution within the discharge chamber. Comparison with chosen experimental temperature profiles shows very good agreement.     

A 100,000‐cd/m2 capacity‐coupled electrodeless discharge backlight with high efficacy for LC TVs

A capacity‐coupled electrodeless Hg discharge lamp has been developed for LC TV backlightings. By applying sinusoidal voltages which are 180° out of phase with a pair of external electrodes, a luminous uniformity of over 84% is attained in two types of lamps whose lengths are 190 and 390 mm. Luminance, efficacy, and input power to the lamp are 114,000 cd/m², 35 lm/W, and 21.5 W when the 390‐mm lamp is driven at 5 MHz. With a frequency below 1.1 MHz, eight 390‐mm lamps, connected in parallel to one another without external ballast impedance, can be driven by using a single inverter.     

Evaluation of additive effects and homogeneity of the starting mixture on the nuclei-growth processes of barium titanate via a solid state route

In an attempt to obtain finest possible microparticles of BaTiO₃ (BT) with highest possible tetragonality via a solid state route, starting mixtures comprising BaCO₃ and TiO₂ were subjected to various pretreatments including addition of glycine and mechanical activation. Reaction processes were monitored by the changes in the weight, crystallinity, and morphology in detail. While mechanical activation with glycine significantly increased the rate of reaction and homogeneity of the particle size of the product, BT, simultaneous particle growth of BT was intolerably acute for micro-electronic devices. The fast particle coarsening was predominated by the coalescence of BT tiny particles formed around titania. A mixture with higher homogeneity was attained by using finer starting materials under wet mixing, avoiding significant mechanical stressing. Particle growth of BT was suppressed to ca. 100 nm to obtain fully crystallized BT particles without significant loss of tetragonality and, hence, close to meet our requirements for MLCCs.     

One-Step Oxidation of Benzene to Phenol over Cu/Ti/HZSM-5 Catalysts

The gas-phase catalytic oxidation of benzene over copper supported on HZSM-5 added with titanium (Cu/Ti/HZSM-5) was carried out by using molecular oxygen as an oxidant. Phenol was effectively produced by the titanium addition to Cu/HZSM-5. The titanium addition to Cu/HZSM-5 induces the easy reduction of Cu²⁺ species to Cu⁺ species in the catalysts, and the produced Cu⁺ species seems to produce the phenol effectively.     

Temperature distribution in Li2O pellets under neutron irradiation

The center temperature of Li₂O pellets under neutron irradiation was measured using an encapsuled pin. The surface temperatures of the pellets and the pellet/cladding heat transfer coefficients were estimated on the basis of the well-known conductivity integral.