Investigation on the Formation of Herringbone Structure in TypeⅡSolar Radio Bursts

We report detailed observation of the“herringbone”of a Type II solar radio burst that occurred on 2010 November 3rd.Data from the Space Weather Prediction Center,National Oceanic and Atmospheric Administration,e-CALLISTO,and Nan?ay Radio Heliograph are analyzed.We determine the brightness temperature and degree of circular polarization of the“herringbone”burst.Correlations between the physical parameters and the“herringbone”are examined.Based on the relationship,this is the first study that suggested this“herringbone”was generated through fundamental plasma.

Intercalation and Stability of Layered Semiconductive Material in Corrosive Environment

进 layeredsemiconductive 材料(MnPS_3 ) 和在腐蚀剂环境(水， HCI 和开的空气) 的产生材料的稳定性的 4 甲基啶(4 皮考啉) 的置闰被调查。粉末 X 光检查衍射(XRD ) 显示水和盐酸的存在极大地在主人的夹层影响了置闰和它的取向的存在形式。大气的环境(开的空气) 在主人材料的夹层影响了客人取向。阶段转变发生了，材料是稳定的。设置的混合物能在三角的单位房间被索引。XRD 模式展出了设置的混合物的锋利的 hkl 思考，它在水和 HCI 里形成了，证实材料在腐蚀剂环境很好水晶、稳定。

中性化离子束在横向磁场中的传输

在真空介质中,由两种磁绝缘离子二极管产生的中性化离子束在横向磁场中B(?)400Gs传输了2m以上的距离 反磁信号以及极化电场测量证实:不论在低β0.01<β<1或在高β情况(1<β<300)下。束传输的机制都是由于的漂移结果。其中β=4πnm_1r_n^2·B^2。是束能量密度与横向磁场能量密度之比。在高β下,我们观察到磁场B向束中的快速扩散。

怀孕期进行ERCP的安全性和有效性

Background Choledocholithiasis during pregnancy increases the risk of morbidit y and mortality for both fetus and mother because of cholangitis and pancreatiti s. ERCP has been advocated as safe and effective in pregnant women, but fetal ra diation exposure is not routinely monitored. The aim of this study was to record fetal exposure to ionizing radiation during ERCP and to assess outcome. Methods Seventeen ERCPs were performed in pregnant women between January 1995 and Augus t 2003. Techniques to minimize fluoroscopy were used, and fluoroscopy times were recorded. Thermoluminescent dosimeters affixed to the skin of the mother were u sed to estimate fetal radiation exposure. Observations Mean gestational age was 18.6 (8.9) weeks (range 5-33 weeks). Mean fluoroscopy time was 14 (13) seconds (range 1-48 seconds). Estimated fetal radiation exposure was 40 (46) mrad (rang e 1-180 mrad).There was a correlation between fluoroscopy time and radiation ex posure, but there was a wide range of radiation exposure for individual fluorosc opy times. Complications included postsphincterotomy bleeding in one patient (co ntrolled by hemoclip placement) and post-ERCP pancreatitis in one patient that necessitated 3 days of hospitalization. Two women developed third-trimester pre eclampsia, and labor was induced in both.Thirteen of the 15 patients who deliver ed were contacted and they confirmed that their child was in good health. Conclu sions ERCP with modified techniques is safe during pregnancy.Dosimetry should be routinely recorded.

CHARACTERIZATION OF NANOSTRUCTURES:TOOLS AND CHALLENGES

Apart from long-known and applied nanostructures like carbon black for tyres or pigments for coatings nanotechnology has created highly sophisticated structures used for nano/molecular electronics,diagnostics,drug delivery, UV-absorbers etc.Often the main question to be solved analytically is the local determination of tiny amounts of chemicals resulting in an ever increasing need for highly sensitive as well as locally resolved techniques.Applications of techniques like mass spectroscopy,transmission el...

The energetic relationship among geoeffective solar flares, associated CMEs and SEPs

Major solar eruptions (flares, coronal mass ejections (CMEs) and solar energetic particles (SEPs)) strongly influence geospace and space weather. Currently, the mechanism of their influence on space weather is not well understood and requires a detailed study of the energetic relationship among these eruptive phenomena. From this perspective, we investigate 30 flares (observed by RHESSI), followed by weak to strong geomagnetic storms. Spectral analysis of these flares suggests a new power-law relationship (r ～ 0.79) between the hard X-ray (HXR) spectral index (before flare-peak) and linear speed of the associated CME observed by LASCO/SOHO. For 12 flares which were followed by SEP enhancement near Earth, HXR and SEP spectral analysis reveals a new scaling law (r ～ 0.9) between the hardest X-ray flare spectrum and the hardest SEP spectrum. Furthermore, a strong correlation is obtained between the linear speed of the CME and the hardest spectrum of the corresponding SEP event (r ～ 0.96). We propose that the potentially geoeffective flare and associated CME and SEP are well-connected through a possible feedback mechanism, and should be regarded within the framework of a solar eruption. Owing to their space weather effects, these new results will help improve our current understanding of the Sun-Earth relationship, which is a major goal of research programs in heliophysics.

Corrosion Penetration and Crystal Structure of AA5022 in HCl Solution and Rare Earth Elements

Al-alloy (AA5022) corrosion penetration (CP) and crystal structure were investigated after running static immersion corrosion tests in 1 mol/L HCl solution and different concentrations of rare earth elements (La3+), (Ce3+) and their combination, at different temperatures. X-ray diffraction (XRD) was used to examine the surface structure before and after immersion, and secondary electron detector (SED) was operated to study surface morphology. In 1 mol/L HCl solution the corrosion penetration increased with increasing temperature and immersion time. The increase of La3+ concentrations up to 1000× 10-6 g/L led to the decrease in the corrosion penetration, and the decrease in Ce3+concentrations up to 50×10-6 g/L decreases the corrosion penetration of the alloy. Mix3 (combination of La3+ and Ce3+) dramatically reduced the corrosion penetration. This suggests that a synergistic effect exists between La3+and Ce3+. The reaction kinetics both in absence and presence of La3+ and Ce3+ and their combination would follow a parabolic rate law. The XRD patterns revealed that the intensities of certain hkl phases are affected. The crystalline structure has not been deformed either before or after testing and there are no additional peaks except that of the as-received alloy. In the case of accelerating CP, the surface morphology shows that the roughness andvoids of surface are increased.

Amplitude-Nth-power squeezing of PB phase coherent states

PB Phase Coherent States are very important quantum states in quantum optics. In order to investigate the amplitude-Nth-power squeezing of PB Phase Coherent States, we introduce the algebraic properties of the PB phase operator and the PB Phase Coherent States which are constructed by PB phase theory. We applied amplitude-Nth-power squeezing theory to define the Amplitude-Nth-Power Squeezing of PB Phase Coherent States and investigate the characteristic of the amplitude-Nth-power squeezing of PB Phase Coherent States. We obtained surprising results, in that the results were different from the other quantum states. As for |Z〉(PB Phase Coherent State), the results show that when Z is a real number there only exists amplitude-Nth-power squeezing of component; when Z is a complex number, there exists amplitude-Nth-power squeezing of component and component; when Z is a pure imaginary number, if N is odd, then there does not exist amplitude-Nth-power squeezing of component, but there exists amplitude-Nth-power squeezing of component and if N is even, then there exists amplitude-Nth-power squeezing of component, but there does not exist amplitude-Nth-power squeezing of component.

Modeling and Simulation of ΔH in Solid State Synthesis of Nanocomposites Al-Cu-Zr

Amorphous structure generated by high-energy ball miller(BM)is often used as a precursor for generating nanocomposites through controlled devitrification.The amorphous forming composition range of ternary Al-Cu-Zr system was calculated using the extended Miedema’s semiempirical model.Eleven compositions of Al-Cu-Zr system showed a wide range of negative enthalpy of mixing(-ΔH^(mix))and amorphization(-ΔH^(amor))among the constituent elements was selected for synthesis by BM.They yielded either nanocomposites of partial amorphous and crystalline structure or no amorphous phase at all in the as-milled condition.The Al_(88)Cu_(6)Zr_(6) alloy with relatively small negativeΔH^(mix)(-0.4 kJ/mol)andΔH^(amor)(-14.8 kJ/mol)became completely amorphous after 120 h of milling.

Application of GC/EIMS in Combination with Semi-Empirical Calculations for Identification and Investigation of Some Volatile Components in Basil Essential Oil

Volatile components in the extracts of basil leaves (Ocimum basilicum L.) were identified by gas chromatography/mass spectrometry (GC/MS) with electron ionization (EI) mode. The major volatile components of basil under investigation are α-pinene, sabinene, β-pinene, d-limonene, eucalyptol, l-linalool and estragole. Electron ionization mass spectra of these compounds have been obtained and investigated. Furthermore, the semi-empirical MNDO [Modified Neglect of Diatomic Overlap] method was used to calculate the thermochemical data for the structural properties of these compounds.

微波磁化

我们已成功地利用微波技术对磁性颗粒进行了磁化和退磁试验.试验结果表明,该技术明显地改善了常规热退磁法因快速加热和冷却过程中经常出现的矿物变异问题.

通过STS对二带超导体MGB_2的π带超导相图研究(英文)

The discovery of the superconductivity with remarkably high critical temperature （TC ～ 39 K） in the binary intermetallic MgB2 compound [1] has given rise to a considerable effort in the condensed matter community in the last three years. Indeed, it promises a higher operating temperature than Nb3Ge with TC = 23 K and unlike the cuprates it shows a lower anisotropy, larger coherence length, higher transparency of the grain boundaries for current flow, which makes it a good candidate for applications.

Physics prospects of the Jinping neutrino experiment

The China Jinping Underground Laboratory(CJPL), which has the lowest cosmic-ray muon flux and the lowest reactor neutrino flux of any laboratory, is ideal to carry out low-energy neutrino experiments. With two detectors and a total fiducial mass of 2000 tons for solar neutrino physics(equivalently, 3000 tons for geo-neutrino and supernova neutrino physics), the Jinping neutrino experiment will have the potential to identify the neutrinos from the CNO fusion cycles of the Sun, to cover the transition phase for the solar neutrino oscillation from vacuum to matter mixing, and to measure the geo-neutrino flux, including the Th/U ratio. These goals can be fulfilled with mature existing techniques. Efforts on increasing the target mass with multi-modular neutrino detectors and on developing the slow liquid scintillator will increase the Jinping discovery potential in the study of solar neutrinos,geo-neutrinos, supernova neutrinos, and dark matter.

Hybridization between microstructure and magnetization improvement in lead and RE co-doped BiFeO_3

The crystal structure,magnetic and electrical properties of Bi_(0.96)Pb_(0.04) FeO_3 and Bi_(0.92)Pb_(0.04)RE_(0.04)FeO_3(RE=La,Sm,Dy and Yb)polycrystalline samples were prepared by the flash autocombustion technique.X-ray diffraction(XRD)measurements show that the rare-earth doped compositions crystallized in rhombohedral symmetry of space group R3 c.The undoped sample consisted needle shape particles while rare earth substitution preferred platelet like particles as clarified from high resolution transmission electron microscopy(HRTEM).Morphological features were examined using field emission scanning electron microscopy(FESEM).Magnetization measurements showed that Yb^(3+) samples possessed the highest room temperature saturation magnetization while when Bi^(3+) ions were substituted by La^(3+) ions,a smaller M_S(0.28 emu/g)was obtained.The coexistence of ferroelectric and magnetic transitions was detected using DSC and χM,indicating the multiferroic characteristics of Bi_(0.92)Pb_(0.04)RE_(0.04)FeO_3 crystallites.The Néel temperature shifted upwards with decreasing the ionic radius of rare earth ion.Nice correlation was established between microstructure,morphology and magnetic properties in view of the contribution of magnetocrystalline and shape anisotropy in the magnetic parameters values.

The cross-correlation of signals and spatial impression in surround sound reproduction

恰好，在喂信号和由左被创造的听觉的空间印象(ASI ) 的跨关联的系数之间的关系离开了在 5.1 隧道包围并且恰好包围扬声器包围健全系统被 psychoacoustic 实验调查。结果为由左右或左右的前面复制显示出那包围扬声器对，听觉的来源宽度(ASW ) 能被控制喂信号到某程度的 crosscorrelation 系数拓宽。在 ASW 和跨关联的系数之间的量的关系频率依赖者。为由一双侧面的扬声器复制，然而， ASW 不能被控制喂信号的跨关联的系数改变。为由前面复制并且仅仅用中央频率同时并且为粉红色的噪音和八音度噪音包围扬声器对 1kHz，听众包封(LEV ) 的一种强壮的感觉能被控制适当地喂信号的 crosscorrelation 系数获得。为有在 2 kHz 和 4 kHz 的中央频率的八音度乐队噪音，然而， LEV 不能被控制喂信号的 crosscorrelation 系数获得。在之间没有唯一的关系的进一步理论的计算和大小表演内部听觉跨关联(IACC ) 并且在 5.1 条隧道的 ASW 包围健全复制，它可能由于 IACC 的算法计算。进一步试验性的确认被需要为评估 ASI 调查 IACC 的适用性。现在的结果将对有用实际包围记录的健全编程和评估。

Analysis of the spatial discrimination threshold of head-related transfer function magnitude

A binaural-loudness-model-based method for evaluating the spatial discrimination threshold of magnitudes of head-related transfer function(HRTF) is proposed.As the input of the binaural loudness model,the HRTF magnitude variations caused by spatial position variations were firstly calculated from a high-resolution HRTF dataset.Then,three perceptualrelevant parameters,namely interaural loudness level difference,binaural loudness level spectra,and total binaural loudness level,were derived from the binaural loudness model.Finally,the spatial discrimination thresholds of HRTF magnitude were evaluated according to just-noticedifference of the above-mentioned perceptual-relevant parameters.A series of psychoacoustic experiments was also conducted to obtain the spatial discrimination threshold of HRTF magnitudes.Results indicate that the threshold derived from the proposed binaural-loudness-modelbased method is consistent with that obtained from the traditional psychoacoustic experiment,validating the effectiveness of the proposed method.

Analysis with binaural auditory model and experiment on the timbre of Ambisonics recording and reproduction

A scheme for analyzing the timbre in spatial sound with binaural auditory model is proposed and the Ambisonics is taken as an example for analysis.Ambisonics is a spatial sound system based on physical sound field reconstruction.The errors and timbre colorations in the final reconstructed sound field depend on the spatial aliasing errors on both the recording and reproducing stages of Ambisonics.The binaural loudness level spectra in Ambisonics reconstruction is calculated by using Moore's revised loudness model and then compared with the result of real sound source,so as to evaluate the timbre coloration in Ambisonics quantitatively.The results indicate that,in the case of ideal independent signals,the high-frequency limit and radius of region without perceived timbre coloration increase with the order of Ambisonics.On the other hand,in the case of recording by microphone array,once the high-frequency limit of microphone array exceeds that of sound field reconstruction,array recording influences little on the binaural loudness level spectra and thus timbre in final reconstruction up to the highfrequency limit of reproduction.Based on the binaural auditory model analysis,a scheme for optimizing design of Ambisonics recording and reproduction is also suggested.The subjective experiment yields consistent results with those of binaural model,thus verifies the effectiveness of the model analysis.