Seco-Abietanoids from Cryptomeria japonica and Their Inhibitory Activity Toward Xanthine Oxidase

Chemistry of Natural Compounds - A new seco-abietanoid, 12-methoxy-7-oxo-6,7-secoabieta-8,11,13-trien-6-oic acid (1), and a known seco-abietanoid,12-hydroxy-6,7-secoabieta-8,11,13-triene-6,7-dial...     

Progress of Jinping Underground laboratory for Nuclear Astrophysics (JUNA)

Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of~(25)Mg(p,γ)~(26)Al,~(19)F(p,α)~(16)O,~(13)C(α,n)~(16)O and ~(12)C(α,γ)~(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given.     

Applications of two-way satellite time and frequency transfer in the BeiDou navigation satellite system

A two-way satellite time and frequency transfer(TWSTFT) device equipped in the BeiDou navigation satellite system(BDS)can calculate clock error between satellite and ground master clock. TWSTFT is a real-time method with high accuracy because most system errors such as orbital error, station position error, and tropospheric and ionospheric delay error can be eliminated by calculating the two-way pseudorange difference. Another method, the multi-satellite precision orbit determination(MPOD)method, can be applied to estimate satellite clock errors. By comparison with MPOD clock estimations, this paper discusses the applications of the BDS TWSTFT clock observations in satellite clock measurement, satellite clock prediction, navigation system time monitor, and satellite clock performance assessment in orbit. The results show that with TWSTFT clock observations, the accuracy of satellite clock prediction is higher than MPOD. Five continuous weeks of comparisons with three international GNSS Service(IGS) analysis centers(ACs) show that the reference time difference between BeiDou time(BDT) and golbal positoning system(GPS) time(GPST) realized IGS ACs is in the tens of nanoseconds. Applying the TWSTFT clock error observations may obtain more accurate satellite clock performance evaluation in the 104 s interval because the accuracy of the MPOD clock estimation is not sufficiently high. By comparing the BDS and GPS satellite clock performance, we found that the BDS clock stability at the 103 s interval is approximately 10.12, which is similar to the GPS IIR.     

Observation of two resonant structures in e+ e- -->pi+ pi- psi(2S) via initial-state radiation at Belle

The cross section for e+ e- --> pi+ pi- psi(2S) between threshold and sqrt[s]=5.5 GeV is measured using 673 fb(-1) of data on and off the Upsilon(4S) resonance collected with the Belle detector at KEKB. Two resonant structures are observed in the pi+ pi- psi(2S) invariant-mass distribution, one at 4361 +/- 9 +/- 9 MeV/c2 with a width of 74 +/- 15 +/- 10 MeV/c2, and another at 4664 +/- 11 +/- 5 MeV/c2 with a width of 48 +/- 15 +/- 3 MeV/c2, if the mass spectrum is parametrized with the coherent sum of two Breit-Wigner functions. These values do not match those of any of the known charmonium states.     

Comment on "direct observation of laser filamentation in high-order harmonic generation"

We argue for a different physical interpretation of the results given in the recent Letter by Painter et al. [Opt. Lett.31, 3471 (2006)] in which an elongated Ti:saphire beam with two distinct waists is considered as direct evidence of laser filamentation. As the pulse power is well below the critical power for self-focusing, the authors pleaded for new examination of the n(2) value for He. A three-dimensional numerical modeling, using the published n(2) value for He, reproduces very well the measured data and invalidates the filamentation hypothesis.     

A New Seco-Abietanoid from the Bark of Cryptomeria japonica

Chemistry of Natural Compounds - A new seco-abietanoid, 12-hydroxy-6,7-seco-abieta-8,11,13-triene-6,7-dioic acid (1), was isolated from the methanol extract of the bark of Cryptomeria japonica. The...     

In situ X‐ray data collection and structure phasing of protein crystals at Structural Biology Center 19‐ID

A prototype of a 96‐well plate scanner for in situ data collection has been developed at the Structural Biology Center (SBC) beamline 19‐ID, located at the Advanced Photon Source, USA. The applicability of this instrument for protein crystal diffraction screening and data collection at ambient temperature has been demonstrated. Several different protein crystals, including selenium‐labeled, were used for data collection and successful SAD phasing. Without the common procedure of crystal handling and subsequent cryo‐cooling for data collection at T = 100 K, crystals in a crystallization buffer show remarkably low mosaicity (<0.1°) until deterioration by radiation damage occurs. Data presented here show that cryo‐cooling can cause some unexpected structural changes. Based on the results of this study, the integration of the plate scanner into the 19‐ID end‐station with automated controls is being prepared. With improvement of hardware and software, in situ data collection will become available for the SBC user program including remote access.     

某型雷达高频舱数字电路测试系统的设计

某型引进装备雷达高频舱部位数字电路随着使用年限的增长,使用频率的增多,故障率逐年增高,已严重制约装备功能的发挥;针对原有备件必须在所属装备测试的验证方式,对装备本身消耗大、验证手段单一,无法满足维修保障需求的问题,开发了基于实物数据采集、分析、测试于一体的自动测试系统,有效地解决了装备作为唯一验证手段的现状,同时大大提高了测试验证的工作效率及验证的准确性,对装备整体功能以及局部功能的检测产生很大的作用,实用性强,适于推广应用。     

Orientations of ZnO grown on GaN

On semipolar epitaxial ZnO grown by chemical vapor deposition consists of two distinct orientations as evidenced by transmission electron microscopy and X‐ray diffraction. The initially grown ZnO on GaN follows the GaN lattice with the epitaxial relationship of // and The other oriented ZnO domains then grow on faceted with and with good coherency with the ‐oriented grains. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)