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T. Klapötke, A. Penger, Carolin Pflüger, Jörg Stierstorfer, M. Sućeska

There are great demands to develop explosives with higher performance accompanied by reduced sensitivities towards external stimuli, higher thermal stability and improved environmental acceptability. This contribution presents modified nitramines, which were investigated by nucleophilic substitution reactions of potassium salts of 5-amino-3-nitro-1,2,4-triazole, 3,5-dinitro-1,2,4-triazole, 3,5-dinitroimidazole, 2,4-dinitroimidazole, 4-amino-3,5-dinitropyrazole, 3,5-dinitropyrazole, 3,4-dinitropyrazole and 3,4,5-trinitropyrazole on 1,3-dichloro-2-nitrazapropane. The energetic compounds were comprehensively characterized and their detonation parameters were calculated by the EXPLO5 code. Heats of formation were calculated by the atomization method using CBS-4M electronic enthalpies. The presented compounds show detonation performances comparable to pentaerythritol tetranitrate (PETN). In addition, they possess high thermal stabilities and low sensitivities, which make them interesting for further investigations and possible applications as insensitive, high-energy dense materials.

F. Boochs, Anna Bentkowska-Kafel, C. Degringy, M. Hauta-Kasari, S. Rizvić, R. Sitnik, A. Trémeau

Abstract The 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) are generally well tolerated as monotherapy. Statins are associated with two important adverse effects, asymptomatic elevation in liver enzymes and myopathy. Myopathy is most likely to occur when statins are administered with other drugs. Statins are substrates of multiple drug transporters (including OAT- -P1B1, BCRP and MDR1) and several cytochrome P450 (CYP) enzymes (including CYP3A4, CYP2C8, CYP2C19, and CYP2C9). Possible adverse effects of statins can occur due to interactions in concomitant use of drugs that substantially inhibit or induce their methabolic pathway. This review summarizes the most important interactions of statins.

Introduction: Therapeutic ultrasound is a physical modality which is constantly expanding range of indications. Analgesic effect of ultrasound is still under discussion. Regardless the extensive application of pulsed ultrasound of low intensity, continuous ultrasound has a better analgesis effect, which is explained by its mechanism of action. Aims: The main research objective of this study was to determine the effect of continuous ultrasound to pain caused by degenerative diseases of the musculoskeletal system in the intensity and duration of ultrasound treatment. Other objectives are entailed determining the correlation between the degree of pain reduction with: location of pain, age, gender and body mass index (BMI). Material and methods: The study included 68 patients with chronic pain localized in the region of the spine or major joints of the extremities, depending on the localization of the degenerative changes. Patients are divided into two groups. The first group was treated with 10 applications of continuous ultrasound with frequency of 1 MHz, intensity 0.4 W/cm2 for 8 minutes, and the other group with 10 applications of ultrasound with frequency of 1 MHz, intensity 0.8 W/cm 2 for 4 minutes. Results and Discussion: Pain intensity was assessed before and after ultrasound therapy performed by subjective visual analogue scale (VAS) for pain, numbered from 0-10, where 0 is the rating for the state of no pain, and 10 grades for severe pain. The average VAS improvement in the first group was 3.97, and 4.74 in second one. The results of F (1.66) = 2.93, p = 0.09 analysis of variance showed no significance difference between the average improvement of two groups. Correlation between the degree of pain reduction showed significance only with BMI, or that higher BMI is associated with a lower degree of pain reduction. The results of this study showed that application of continuous ultrasound in patients with chronic pain, caused by degenerative changes in the musculoskeletal system, led to a significant reduction in pain. Different intensity and duration of ultrasound application showed no significant effect on the degree of pain reduction. Body mass index showed significant negative correlation with the degree of pain reduction, but age, gender and location of pain did not show significant correlation.

M. Hollander, J. Sage, Alexandria J. Greenler, Joshua Pendl, T. Avčin, G. Espada, M. Beresford, M. Henrickson et al.

Hung Q. Nguyen, Jim S. Whittington, John C. Devlin, Ha L. Vu, N. Vu, E. Custovic

The TIGER-3 radar is being developed as an “all digital” radar with 20 integrated digital transceivers, each connected to a separate antenna. Using phased array antenna techniques, radiated power is steered towards a desired direction based on the relative phases within the array elements. This paper proposes an accurate phase measurement method to calibrate the phases of the radio output signals using Field Programmable Gate Array (FPGA) technology. The method sequentially measures the phase offset between the RF signal generated by each transceiver and a reference signal operated at the same frequency. Accordingly, the transceiver adjusts its phase in order to align to the reference phase. This results in accurately aligned phases of the RF output signals and with the further addition of appropriate phase offsets, digital beamforming (DBF) can be performed steering the beam in a desired direction. The proposed method is implemented on a Virtex-5 VFX70T device. Experimental results show that the calibration accuracy is of 0.153 degrees with 14 MHz operating frequency.

E. Custovic, D. Elton, J. Whittington, J. Devlin, A. Console, B. Bienvenu, A. McDonald, H. Nguyen

C. S. Souza, V. Lins, D. Silveira, C. Costa, Ronaldo Cardoso Júnior, F. Campos, Alexandre Queiroz Bracarense

Duplex stainless steels (DSS's) have been placed as an excellent alternative for applications where high corrosion resistance and high mechanical strength are required. However, the DSS's, including the lean duplex stainless steels, present lower weldability than the austenitic stainless steels. This study aims to evaluate the corrosion resistance of welded joints using multipass welding of lean duplex stainless alloy UNS S32304 plates 22 mm thick, using the SMAW, GMAW and FCAW consumables with two types of chemical composition, 22%Cr9%Ni3%Mo and 23%Cr7%Ni, giving a total of six experiments. The welded joints were evaluated using the anodic potentiodynamic polarization technique to determine the pitting potential of the material. The electrolyte studied was 3.5% w/v sodium chloride aqueous solution. The lean duplex steel welded by GMAW process with consumable with 22%Cr9%Ni3%Mo showed the best behavior against corrosion in saline solution. The root of the weld region had the highest pitting potential compared to the top of the welded joints. The lean duplex steel joints welded using FCAW process showed a behavior characteristic of general corrosion in the medium of saline solution, unlike the other samples.

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