Implementation of the inverse circular radon transform‐based imaging approach for breast cancer screening

In this article, the approach based on the inverse circular radon transform technique (ICRT) is proposed to obtain the image of the breast cancer screening based on microwaves. A simplified numerical breast model is constructed and computational results are obtained with the use of synthetic aperture radar principle. A tumor phantom is produced and the experimental results are acquired by using sand, screw and phantoms with the use of an experimental setup prototype that is also presented in this study. The simulation results are verified and validated by experimental results. The resultant images generated using the simulated and experimental data show a good agreement with the designed scenarios.     

Storage stability of cod liver oil organogels formed with beeswax and carnauba wax

In this study, organogels of cod liver oil (CLO) with beeswax (BW) and carnauba wax (CW) were prepared, and compared with a commercial margarine (CM). Oil binding capacities (OBC) of BW organogels were over 99%, while CW had a maximum OBC value of 91.28%. Crystal formation time of BW was shorter. Although the highest solid fat content (SFC) was in the 10% CW containing sample (8.69%), it was 28.99% in the CM sample at 20 °C. The peak melting temperature of CM was 43.70 °C, and BW organogel at 3% addition had the closest values (45.42 °C). Firmness and stickiness values of the organogels were lower than that of CM sample. No significant change in the texture parameters during storage was detected, indicating good stability. There was no hurdle against oxidation by organogelation during storage. This study has shown that CLO organogels can be suitable spreadable products.     

Controller reduction by H∞-balancedtruncation

H_∞-balanced truncation may be used to obtain reduced-order plants or controllers. The plant (possibly unstable) is compensated using a particular robustly stabilizing controller. The two Riccati equations involved are then used to define a set of closed-loop input-output invariants called the H_∞-characteristic values. That part of the plant or controller corresponding to small H_∞-characteristic values is discarded to give a reduced-order plant or controller. By exploiting an intimate connection with coprime factorization, a simple a priori test is derived for the ability of such a reduced-order controller to stabilize the full-order plant. The performance of the resulting closed-loop may also be bounded a priori, i.e. in terms of the prespecified level of robustness and the discarded H_∞-characteristic values     

The near-net-shape manufacturing of affordable titanium components for the M777 lightweight howitzer

The U.S. Marines’ and U.S. Army’s next-generation, titanium-intensive M777 howitzer offers reduced weight, increased mobility, and improved survivability over its aging, M198 steel-based predecessor. The National Center for Excellence in Metalworking Technology (NCEMT), operated by Concurrent Technologies Corporation, is helping to meet M777 program goals for cost, performance, and production schedule by developing near-net-shape manufacturing routes for traditionally machined and welded components. Under two projects sponsored by the Navy Manufacturing Technology Program, the NCEMT has developed investment cast spade and saddle components as well as flowformed tubes and forged bell housings. This paper summarizes the results of the two ongoing projects. For more information, contact Kevin L. Klug, Concurrent Technologies Corporation, 100 CTC Drive, Johnstown, PA 15904; (814) 269-2868; e-mail klugk@ctc.com.     

Investigation of explosive welding parameters and their effects on microhardness and shear strength

The aim of this study was to investigate the strength of explosive welded metals with the same chemical compositions. Different welding interfaces (straight, wavy and continuous solidified-melted) were used with changing explosive welding parameters [stand-off distance (s), explosive loading (R) and anvils]. Joined metals were investigated under heat-treated and untreated conditions. Results on the microstructure, microhardness, tensile shear strength and bending tests are reported. According to the experimental results, the effect of the anvil on the explosive welding process was only the joining or not-joining performance. It was shown that the bonding interface changed from a straight to a wavy structure when the explosive loading and stand-off distance were increased. For wavy interfaces, when the explosive loading was increased the wavy length and amplitude increased. Results of tensile shear and bending tests showed that heat-treated specimens have more strength than untreated samples. According to tensile shear test results, straight and wavy interfaces had similar strength. In addition, in bending tests of untreated specimens it was shown that the bending zone had some cracks.     

Convenient preparation of methyl 10-(1,3,2-Oxazaphospholidin-2-one)undecanoate and methyl 10-(1,3,2-diazaphospholidin-2-one)undecanoate

Synthesis and spectral studies of methyl 10-(1,3,2-oxazaphospholidin-2-one)undecanoate and methyl 10-(1,3,2-diazaphospholidin-2-one)undecanoate are reported. These fatty products were obtained in excellent yields when methyl 10-hydroxyundecanoate was reacted with phosphorus oxychloride, and the resultant intermediate was treated with aminoethanol and ethylenediamine in two different reactions.     

Characterization of Sultaniye grape (Vitis vinifera L. cv. Sultana) polyphenol oxidase

Polyphenol oxidase (PPO) was extracted from Sultaniye grapes grown in Turkey, and its characteristics in terms of pH and temperature optima, thermal inactivation, kinetic parameters and potency of some PPO inhibitors were studied. Optimum pH and temperature for grape PPO were found to be 3.4 and 30 °C, using catechol as substrate. K_m and V_max values were found to be 44.5 ± 5.47 mm and 0.695 ± 0.0353 OD₄₁₀ min^?1, respectively. Four inhibitors were tested in this study and the most potent inhibitor was sodium metabisulphite, followed by ascorbic acid. From the thermal inactivation studies in the range of 65–80 °C, the half‐life values of the enzyme ranged between 2.6 and 49.5 min. Activation energy (E_a) and Z values were calculated to be 208.5 kJ mol^?1 (r² = 0.9544) and 10.95 °C (r² = 0.9517), respectively.     

Sulfite determination using sulfite oxidase biosensor based glassy carbon electrode coated with thin mercury film

The preparation of sulfite biosensor by immobilization of sulfite oxidase on a glassy carbon electrode coated with mercury thin film is described. Dissolved oxygen can be readily reduced at the glassy carbon electrode coated with mercury thin film. The working principle of the biosensor was based on monitoring decrease in the peak current due to the depletion in dissolved oxygen concentration according to the reaction of sulfite oxidase.