Polarized proton target for RI Beam experiments

We have constructed a polarized proton solid target system for radioactive nuclear beam experiments at the Center for Nuclear Study, the University of Tokyo. The proton polarization is based on an electron population difference in a photo-excited triplet state of pentacene molecule. The target system was completed in 2003 and applied to a RI beam experiment in 2003 and 2005 by using the projectile fragment separator, RIPS at RIKEN. The maximum polarization reached 20% under the condition of T=100 K and B=0.09 T. Overview of the polarized target and its application in physics experiments at RIPS and RIBF of RIKEN are presented.     

Playback performance of perpendicular magnetic recording tape media for over-50-TB cartridge by facing targets sputtering method

Perpendicular magnetic recording tape medium with laminated soft magnetic underlayers was successively formed on a 4.5 μm thin plastic film by the facing targets sputtering method at room temperature. The tape medium showed extremely high SNR values with sharp transitions in playback tests by a drum tester, compared to a linear format commercial tape medium. An areal density of 45.0 Gb/in.² of perpendicular tape medium was confirmed by a high-resolution contact tester. These results suggest that the perpendicular recording tape medium by the facing targets sputtering method is a promising candidate for a tape cartridge of over 50-TB.     

Untersuchungen zur Ermittlung der Tiefenverteilung der primären Ionisationen in dicken Zwei-Element-Targets bei Beschuß mit Elektronen aus dem Energiebereich unterhalb 30 keV. Teil 1

Es werden methodische Untersuchungen zur Entwicklung eines Monte-Carlo-Programmes zur Berechnung der Tiefen-verteilung der primären Ionisationen auf der Grundlage der Vielfachstreutheorie von Molière beschrieben. Anhand aus-gewählter Zwei-Element-Targets wird die Leistungsfähigkeit von drei Varianten eines entsprechenden Elektronentrans-portmodells untersucht. Unter Benutzung der entwickelten Elektronentransportmodelle werden für die Elektronenstrahl-mikroanalyse interessierende Größen, wie Rückstreukoeffizient, Rückstreufaktor und Absorptionskorrektion, berechnet.     

Evidence of Dynamical Fluctuation of Target Residues in Relativistic Nuclear Interaction at 14.5 AGeV

An analysis of data of target fragments of ²⁸Si-AgBr (at 14.5 AGeV) reveals the existence of emission asymmetry in the azimuthal plane, which is found to depend on the number of target fragments. The comparison with the data of ³²S-AgBr (at 200 AGeV) and ¹⁶O-AgBr (at 60 AGeV) interactions indicates that emission asymmetry depends on the projectile mass and energy.     

Transmutation of 129I, 237Np, 238Pu, 239Pu, and 241Am using neutrons produced in target-blanket system ‘Energy plus Transmutation’ by relativistic protons

Target-blanket facility ‘Energy + Transmutation’ was irradiated by proton beam extracted from the Nuclotron Accelerator in Laboratory of High Energies of Joint Institute for Nuclear Research in Dubna, Russia. Neutrons generated by the spallation reactions of 0.7, 1.0, 1.5 and 2 GeV protons and lead target interact with subcritical uranium blanket. In the neutron field outside the blanket, radioactive iodine, neptunium, plutonium and americium samples were irradiated and transmutation reaction yields (residual nuclei production yields) have been determined using γ-spectroscopy. Neutron field's energy distribution has also been studied using a set of threshold detectors. Results of transmutation studies of ¹²⁹I, ²³⁷Np, ²³⁸Pu, ²³⁹Pu and ²⁴¹Am are presented.      

环境监测分析中校准曲线可靠性和检验方法的探讨

介绍了环境监测分析中校准曲线的分类、拟合方法和应用范围,提出了对拟合校准曲线进行可靠性检验的设想和建议的经验指标。如相对剩余标准差、截距、斜率检验、失拟方差检验等,这些方法在实际监测分析中具有一应用价值。     

High-throughput lipidomics analysis to discover lipid biomarkers and profiles as potential targets for evaluating efficacy of Kai-Xin-San against APP/PS1 transgenic mice based on UPLC–Q/TOF–MS

Lipid metabolism has a significant function in the central nervous system and Alzheimer's disease (AD) is an age-related senile disease characterized by central nerve degeneration. The pathological development of AD is closely related to lipid metabolism disorders. To reveal the influence of Kai-Xin-San (KXS) on lipid metabolism in APP/PSI transgenic mice and potential therapeutic targets for treating AD, brain tissue samples were collected and analyzed by high-throughput lipidomics based on UPLC–Q/TOF-MS. The collected raw data were processed by multivariate data analysis to discover the potential biomarkers and lipid metabolic profiles. Compared with the control wild-type mouse group, nine potential lipid biomarkers were found in the AD model group, of which seven were up-regulated and two were down-regulated. Orally administrated KXS can reverse the changes in these potential biomarkers. Compared with the model group, a total of six differential metabolites showed a recovery trend and may be potential targets for KXS to treat AD. This study showed that high-throughput lipidomics can be used to discover the perturbed pathways and lipid biomarkers as potential targets to reveal the therapeutic effects of KXS.