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Abstract: The high repetition rate satellite laser ranging (SLR) measurements to the fast spinning satellites contain a frequency signal caused by the rotational motion of the corner cube reflector (CCR) array. The spectral filter, developed here, is based on the Lomb algorithm, and is tested with the simulated and the observed high repetition rate SLR data of the geodetic satellite Ajisai (spin period ∼2s). The filter allows for the noise elimination from the SLR data, and for identification of the returns from the single CCRs of the array – even for the low return rates. Applying the spectral filter to the simulated SLR data increases the S/N ratio by a factor 40–45% for all return rates. Filtering out the noise from the observed data strengthens the frequency signal by factor of ∼25 for the low return rates, which significantly helps to determine the spin phase of the satellite. The spectral filter is applied to the Graz SLR data and the spin rates of Ajisai are determined by two different methods: the frequency analysis and the phase determination of the spinning retroreflector array. The analysis of more than 8years of the Graz SLR measurements indicates an exponential spin rate trend: f =0.67034 exp(−0.0148542 Y) [Hz], RMS=0.085mHz, where Y is the year since launch. The highly accurate spin rate information demonstrates periodic changes related to the precession of the orbital plane of Ajisai, as it determines the amount of energy received by the satellite from the Sun. The rate of deceleration of Ajisai is not constant: the half life period of the satellite’s spin oscillates around 46.7years with an amplitude of about 5years. [Copyright &y& Elsevier]

Abstract: The design of the retroreflector array (RRA) of the fast spinning Experimental Geodetic Satellite (Ajisai) allows to determine orientation of its spin axis by means of frequency analysis. Moving spectral analysis (MSA) of the simulated Satellite Laser Ranging (SLR) data gives information about frequencies which can be obtained for the whole range of the incident angle between the laser beam vector and the spin axis of the spacecraft. This frequency signal changes as the incident laser beam crosses consecutive rings of the RRA. Knowledge about spectral response of Ajisai allows successful application of MSA to the Graz 2kHz SLR data (2003–2011) and determination of 78 spin axis orientation values. The obtained results show that the spin axis of Ajisai is stable around RA 15h22m24.0s, Dec 88.05° (J2000.0 celestial reference frame), and is almost parallel to the spin axis of Earth. [Copyright &y& Elsevier]

Abstract: Satellite Laser Ranging (SLR) is a powerful technique able to measure spin rate and spin axis orientation of the fully passive, geodetic satellites. This work presents results of the spin determination of LARES – a new satellite for testing General Relativity. 529 SLR passes measured between February 17 and June 9, 2012, were spectrally analyzed. Our results indicate that the initial spin frequency of LARES is f0 =86.906mHz (RMS=0.539mHz). A new method for spin axis determination, developed for this analysis, gives orientation of the axis at RA=12h22m48s (RMS=49m), Dec=−70.4° (RMS=5.2°) (J2000.0 celestial reference frame), and the clockwise (CW) spin direction. The half-life period of the satellite’s spin is 214.924days and indicates fast slowing down of the spacecraft. [Copyright &y& Elsevier]

Abstract: The Graz 2kHz Satellite Laser Ranging (SLR) measurements allow determination of the spin axis orientation of the geodetic satellite Ajisai. The high repetition rate of the laser makes it possible to determine the epoch time when the laser is pointing directly between two corner cube reflector (CCR) rings of the satellite. Identification of many such events during a few (up to 3) consecutive passes allows to state the satellite orientation in the celestial coordinate system. Six years of 2kHz SLR data (October 2003–October 2009) delivered 331 orientation values which clearly show precession of the axis along a cone centered at 14h56m2.8s in right ascension and 88.512° in declination (J2000.0 celestial reference frame) and with an half-aperture angle θ of 1.405°. The spin axis precesses with a period of 117days, which is equal to the period of the right ascension of the ascending node of Ajisai’s orbit. We present a model of the axis precession which allows prediction of the satellite orientation – necessary for the envisaged laser time transfer via Ajisai mirrors. [Copyright &y& Elsevier]

This paper describes synthetic approaches to extraordinarily long oligothiophenes, which correspond to mono-disperse polymers. The most successful approach is a combination of a random coupling reaction of mono- and diethynylsexithiophenes and a subsequent sodium sulfide-induced cyclization reaction of the diacetylene parts to thiophene rings, forming a series of long oligothiophenes Oct-nT up to the 48-mer. The systematic study of the Oct-nT series reveals that the effective conjugation length of conjugated polythiophenes extends to around 20 thiophene units. [Copyright &y& Elsevier]

Abstract: Satellite Laser Ranging (SLR) is a powerful and efficient technique to measure spin parameters of satellites equipped with corner cube reflectors. We obtained spin period determination of the satellite AJISAI from SLR data only: 17246 pass-by-pass estimates from standard 1–15Hz SLR data (14/Aug/1986–30/Dec/2008) and 1444 pass-by-pass estimates (9/Oct/2003–30/Dec/2008) from data of the first 2kHz SLR system from Graz, Austria. A continuous history of the slowing down of AJISAI spin is derived from frequency analysis, and corrected for the apparent effects. The apparent corrections, elaborated here, allowed very accurate determination of AJISAI initial spin period: 1.4855±0.0007 [s]. The paper identifies also non-gravitational effects as a source of the periodical changes in the rate of slowing down of the satellite. [Copyright &y& Elsevier]

Abstract: Novel long oligothiophenes incorporated with four fullerenes (2C 60 –16T–2C 60 and 2C 60 –24T–2C 60 ) have been synthesized with the aim of developing good single-component photovoltaic materials. The tetracosithiophene derivative 2C 60 –24T–2C 60 , despite its giant structure, is rather more tractable regarding solubility than the hexadecithiophene derivative 2C 60 –16T–2C 60 . The electronic absorption and emission spectra of 2C 60 –24T–2C 60 indicated no electronic interaction in the ground state but efficient intramolecular electron transfer in the excited state. The sandwich device of the Al/2C 60 –24T–2C 60 /Au structure showed a marked photocurrent upon illumination with monochromatic light from the Al side. The incident-photon to converted-electron ratio (IPCE) is 14%. [Copyright &y& Elsevier]

Abstract: Background: Reperfusion of ischemic tissues results in the formation of toxic reactive oxygen species (ROS), such as superoxide anion, hydroxyl radicals, hydroperoxide, and peroxynitrite. ROS are potent oxidizing agents, capable of damaging cellular membranes by lipid peroxidation. In the present study, we applied an in vivo electron paramagnetic resonance (EPR)/spin probe and an ex vivo EPR technique to provide direct evidence of ROS following experimentally induced small bowel ischemia/reperfusion (I/R) injury. Materials and Methods: We used a rat model of small bowel I/R injury to explore the possibility that MnM2Py4P or Mn-salen can prevent the accumulation of ROS species following experimentally induced I/R injury. We examined the ability of MnM2Py4P and Mn-salen to scavenge radicals in living Sprague-Dawley (SD) rats using an in vivo and an ex vivo EPR technique with a spin probe. Results: The CP decay rates in the MnM2Py4P- and Mn-salen-treated rats were significantly higher than those in the untreated rats and almost equal to those in sham group rats. There were no significant differences between the MnM2Py4P-treated group and the Mn-salen-treated group. Superoxide scavenging activities (SSA) in the MnM2Py4P- and EUK-8-treated group were higher than those in the untreated group and almost equal to the sham group. Conclusion: The present study suggested that the protective effects of MnM2Py4P and Mn-salen against small bowel IR injury were mediated by the inhibition of O2, H2O2, and NO production. [Copyright &y& Elsevier]

Abstract: The present study demonstrated the feasibility of monitoring nitric oxide (NO) and pO2 levels under ischemic conditions associated with small bowel ischemia/reperfusion (I/R) injury through the use of selective electrodes for NO and oxygen molecules. NO levels gradually increased during ischemia. When reperfusion was started, the NO level decreased suddenly and returned to pre-ischemia values within 10 minutes. After clamping, pO2 decreased rapidly. When reperfusion was started, pO2 increased suddenly, returning to pre-ischemia values within 10 minutes. We concluded that it is feasible to monitor NO and pO2 levels under ischemic conditions of small bowel I/R injury through the use of electrodes selective for NO and oxygen molecules. [Copyright &y& Elsevier]

Electrocrystallizaion of MDT-TSF (methylenedithiotetraselenafulvalene) in the presence of (n-Bu4N)AuI2, (n-Bu4N)PF6, or a mixture of Cu(SCN), KSCN, and 18-crown-6-ether as a supporting electrolyte gave (MDT-TSF)-X salts (X=AuI2, PF6, or Cu(NCS)2). X-ray structural analyses revealed that the salts adopt various types of crystal structures depending on the counter anion involved; the AuI2 salt takes a characteristic uniform stacking structure, the PF6 salt θ-type, and the Cu(NCS)2 salt κ-type structure. Regardless of the structure type, all the salts are highly conductive at room temperature (>102 S cm−1) and retain metallic down to low temperature. Of them, the AuI2 salt having a high conductivity of 2000 S cm−1 at room temperature showed a superconducting transition at 4.5 K. [Copyright &y& Elsevier]