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Transition from Electric Rotation to Chiral Mode in 135Nd

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Chinese Physics Letters 2012年第7期29卷 60-63页

作者： QI Bin LI Jian WANG Shou-Yu ZHANG Jing ZHANG Shuang-Quan Shandong Provincial Key laboratory of Optical Astronomy and solar-terrestrial environment School of Space Science and PhysicsShandong University at WeihaiWeihai 264209 College of Physics Jilin UniversityChangchun 130012 State Key laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871

With the inputs from the relativistic mean field approach,the observed energy spectra and electromagnetic properties are well reproduced for the yrast band of odd-A nucleus 135Nd by the particle rotor *** on the analysis of the angular momentum components,it is further illustrated that this yrast band contains two stages of rotational mode,i.e.,the electric rotation for low-spin region and chiral mode for high-spin region.

关键词： Transition rotation Chiral

Quantitative analysis modeling for the Chem Cam spectral data based on laser-induced breakdown spectroscopy using convolutional neural network

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Plasma Science and Technology 2020年第11期22卷 81-90页

作者： Xueqiang CAO Li ZHANG Zhongchen WU Zongcheng LING Jialun LI Kaichen GUO School of Mechanical Electrical&Information EngineeringShandong UniversityWeihai 264209People's Republic of China Shandong Provincial Key laboratory of Optical Astronomy and solar-terrestrial environment Institute of Space SciencesShandong UniversityWeihai 264209People's Republic of China

Laser-induced breakdown spectroscopy(LIBS)has been applied to many fields for the quantitative analysis of diverse *** the prediction accuracy of LIBS regression models is still of great significance for the Mars exploration in the near *** this study,we explored the quantitative analysis of LIBS for the one-dimensional Chem Cam(an instrument containing a LIBS spectrometer and a Remote Micro-Imager)spectral data whose spectra are produced by the Chem Cam team using LIBS under the Mars-like atmospheric *** constructed a convolutional neural network(CNN)regression model with unified parameters for all oxides,which is efficient and *** that has the excellent capability of feature extraction can effectively overcome the chemical matrix effects that impede the prediction accuracy of regression ***,we explored the effects of four activation functions on the performance of the CNN *** results show that the CNN model with the hyperbolic tangent(tanh)function outperforms the CNN models with the other activation functions(the rectified linear unit function,the linear function and the Sigmoid function).Secondly,we compared the performance among the CNN models using different optimization *** CNN model with the stochastic gradient descent optimization and the initial learning rate?=?0.0005 achieves satisfactory performance compared to the other CNN ***,we compared the performance of the CNN model,the model based on support vector regression(SVR)and the model based on partial least square regression(PLSR).The results exhibit the CNN model is superior to the SVR model and the PLSR model for all *** on the above analysis,we conclude the CNN regression model can effectively improve the prediction accuracy of LIBS.

关键词： laser-induced breakdown spectroscopy convolutional neural network activation function optimization method quantitative analysis

Influence of aquatic plants on the hydrogen isotope composition of sedimentary long-chain n-alkanes in the Lake Qinghai region, Qinghai-Tibet Plateau

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Science China Earth Sciences 2016年第7期59卷 1368-1377页

作者： LIU Wei Guo YANG Hong WANG Huan Ye YAO Yuan WANG Zheng CAO Yun Ning State Key laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences School of Human Settlements and Civil Engineering Xi'an Jiaotong University laboratory for terrestrial environment Department of Science and Technology College of Arts and Sciences Bryant University

The hydrogen isotopic composition(δD) of leaf wax long-chain n-alkanes(C27, C29, and C31) from lacustrine sediments has been widely applied to reconstruct terrestrial paleoclimatic and paleohydrological changes. However, few studies have addressed whether the aquatic-derived n-alkanes can affect the δD values of lake sedimentary long-chain n-alkanes, which are usually regarded as a recorder of the terrestrial hydrological signals. Here we systematically investigated δD values of long-chain n-alkanes from modern aquatic plants, both near-shore and off-shore surface sediments, surrounding terrestrial plant litters, as well as river water and lake water in Lake Qinghai and its satellite lakes on the northeastern Qinghai-Tibet Plateau. Our data showed that(i) δD values of long-chain n-alkanes from aquatic plants varied from-184‰ to-132‰ for n-C27, from-183‰ to-138‰ for n-C29, and from-189‰ to-130‰ for n-C31, respectively, with no significant differences among the three n-alkanes homologues;(ii) δD values of long-chain n-alkanes from aquatic plants were generally more positive than those from surrounding terrestrial plants, possibly because that they recorded the D-enrichment of lake water in this semi-arid region;(iii) δD values of long-chain n-alkanes from surface sediments showed significant differences among the three n-alkanes homologues, due to the larger aquatic input of n-C27 to the sedimentary lipid pool than that of n-C31, and(iv) n-C27 δD values of near-shore aquatic plants and near-shore sediments are more negative than those from off-shore as a result of lower δD values of near-shore lake water. Our findings indicate that in this region(i) the offset between sedimentary n-C27 and n-C31 δD values(ΔδDC27-C31) could potentially be used to evaluate if sedimentary long-chain n-alkanes are derived from a single source;(ii) while δD values of n-C27 may be influenced by lake water hydrological changes, sedimentary n-C31 is derived predominantly from terrestrial plan

关键词： Hydrogen isotope Long-chain n-alkanes Aquatic plants Paleohydrology proxy Lake Qinghai

The semiannual variation of transpolar arc incidence and its relationship to the Russell–McPherron effect

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Earth and Planetary Physics 2020年第6期4卷 619-626页

作者： Tao Tang Jun Yang QuanQi Shi AnMin Tian Shi-Chen Bai Alexander William Degeling SuiYan Fu JingXian Liu Tong Shao ZeYuan Sun Shandong Key laboratory of Optical Astronomy and solar-terrestrial environment School of Space Science and PhysicsInstitute of Space SciencesShandong UniversityWeihai Shandong 264209China Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China

Earth’s aurora is a luminescent phenomenon generated by the interaction between magnetospheric precipitating particles and the upper atmosphere;it plays an important role in magnetosphere–ionosphere(M-I)*** transpolar arc(TPA)is a discrete auroral arc distributed in the noon-midnight direction poleward of the auroral oval and connects the dayside to the nightside sectors of the auroral *** the seasonal variation of TPA events can help us better understand the long-term variation of the interaction between the solar wind,the magnetosphere,and M-I ***,a statistical study of the seasonal variation of TPA incidence has not previously been carried *** this paper,we have identified 532 TPA events from the IMAGE database(2000–2005)and the Polar database(1996–2002),and calculated the incidence of TPA events for different *** find a semiannual variation in TPA *** peaks in the incidence of TPAs occur in March and September;a less pronounced peak appears in *** also examine seasonal variation in the northward interplanetary magnetic field(IMF)over the same time *** intensity and occurrence rate of the northward IMF exhibit patterns similar to that of the TPA *** studied IMF Bz before TPA onset,we find that strong and steady northward IMF conditions are favorable for TPA *** suggest that the semiannual variation observed in TPA incidence may be related to the Russell–McPherron(R-M)effect due to the projection effect of the IMF By under northward IMF conditions.

关键词： transpolar arc incidence interplanetary magnetic field Russell-McPherron effect semiannual variation

Damping and power spectra of quasi-periodic intensity disturbances above a solar polar coronal hole

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Research in Astronomy and Astrophysics 2016年第6期16卷 85-92页

作者： Fang-Ran Jiao Li-Dong Xia Zheng-Hua Huang Bo Li Hui Fu Ding Yuan Kalugodu Chandrashekhar Shandong Provincial Key laboratory of Optical Astronomy and solar-terrestrial environment Institute of Space Sciences Shandong University Weihai 264209 Shandong China Jeremiah Horrocks Institute University of Central Lancashire Preston PR1 2HE UK

We study intensity disturbances above a solar polar coronal hole that can be seen in the AIA 171 and 193 ＆ passbands, aiming to provide more insights into their physical nature. The damping and power spectra of the intensity disturbances with frequencies from 0.07 mHz to 10.5 mHz are investigated. The damping of the intensity disturbances tends to be stronger at lower frequencies, and their damping behavior below 980＂（for comparison, the limb is at 945＂） is different from what happens above. No significant difference is found between the damping of the intensity disturbances in the AIA 171 ~ and that in the AIA 193 ]k. The indices of the power spectra of the intensity disturbances are found to be slightly smaller in the AIA 171/~ than in the AIA 193 ~, but the difference is within one standard deviation. An additional enhanced component is present in the power spectra in a period range of 8-40 min at lower heights. The power spectra of a spicule is highly correlated with its associated intensity disturbance, which suggests that the power spectra of the intensity disturbances might be a mixture of spicules and wave activities. We suggest that each intensity disturbance in the polar coronal hole is possibly a series of independent slow magnetoacoustic waves triggered by spicular activities.

关键词： Sun: corona- Sun: waves -- Sun: turbulence -- method: observational

Aerosol optical properties derived from simultaneous sunphotometer and aureolemeter measurements in Lhasa

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Journal of environmental Sciences 2000年第4期12卷 439-443页

作者： BAI Yu-bo SHI Guang-yu Koichi Tamura Takashi Shibata Yasunobu Iwasaka Kaneta Shin′ichi Takamura Tamio State Key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Inst itute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China solar terrestrial environment laboratory Nagoya UniversityNagoyaJapan Center for environmental Remote Sensing Chiba UniversityChibaJapan

In order to obtain some aerosol properties in Tibetan Plateau atmosphere, simultaneous measurements of aerosols by use of a sunphotometer and an aureolementer were performed in the summer of 1998 in Lhasa(29.65°N, 91.13°E). Optical depth, volume size distribution and phase\|function of aerosols were obtained from the measurements. Religious activities can have an effect on optical depth in Lhasa. The daily average aerosol optical depth( λ =500 nm) is less than 0.2. The diurnal variations of aerosol optical depth are relatively small during the period of summer. The maximal value of the mode radius in the volume size distribution are about 0.4, 2.0 and 4.0μm.

关键词： sunphotometer aureolemeter optical depth aerosol volume spectrum phase function

Identification of ten new Galactic HII regions

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Science China(Physics,Mechanics & Astronomy) 2010年第6期53卷 1144-1152页

作者： RUAN GuiPing 1,2 & SHI WeiBin 1,2 1 Shandong Provincial Key laboratory of Optical Astronomy and solar-terrestrial environment,School of Space Science and Physics,Shandong University at Weihai,Weihai 264209,China 2 Key laboratory of Optical Astronomy,National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100012,China Shandong Provincial Key laboratory of Optical Astronomy and solar-terrestrial environment School of Space Science and Physics Shandong University at Weihai Weihai China Key laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing China

We discovered ten large HII regions in the Sino-German λ6 cm polarization survey of the Galactic plane. They have been identified according to their flat spectral indexes and the high ratio between the 60 μm infrared emission and the λ6 cm emission. The integrated flux densities as well as the sizes of these sources are given at 4800 MHz. Cross-identifications are made with other major radio catalogs.

关键词： radio continuum general-methods observational-HII regions

Mineralogy of Chang'e-4 landing site:preliminary results of visible and near-infrared imaging spectrometer

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Science China(Information Sciences) 2020年第4期63卷 195-206页

作者： Jian CHEN Zongcheng LING Le QIAO Zhiping HE Rui XU Lingzhi SUN Jiang ZHANG Bo LI Xiaohui FU Changqing LIU Xiaobin QI Shandong Key laboratory of Optical Astronomy and solar-terrestrial environment School of Space Science and PhysicsInstitute of Space Sciences Shandong University Key laboratory of Space Active Opto-Electronics Technology Shanghai Institute of Technical PhysicsChinese Academy of Sciences Hawai'i Institute of Geophysics and Planetology Department of Earth Sciences University of Hawai'i at Manoa

The exploration of mafic anomaly in South Pole-Aitken(SPA, the largest confirmed) basin on the Moon provides important insights into lunar interior. The landing of Chang’e-4(CE-4) and deployment of Yutu-2 rover on the discontinuous ejecta from Finsen crater enabled in-situ measurements of the unusual mineralogy in the central portion of SPA basin with visible and near-infrared imaging spectrometer(VNIS).Here we present detailed processing procedures based on the level 2B data of CE-4 VNIS and preliminary mineralogical results at the exploration area of Yutu-2 rover. A systematic processing pipeline is developed to derive credible reflectance spectra, based on which several spectral and mineral indices are calculated to constrain the mafic mineralogy. The mafic components in the soils and boulder around CE-4 landing site are concluded as clinopyroxene-bearing with intermediate composition and probably dominated by pigeonite although the possibility of mixing orthopyroxen(OPX) and calcic clinopyroxene(CPX) also exists. These mineralogical results are more consistent with a petrogenesis that the CE-4 regolith and rock fragment are derived from rapid-cooling magmatic systems and we interpret that the materials at the CE-4 landing site ejected from Finsen crater are probably recrystallized from impact melt settings.

关键词： Chang’e-4 visible and near-infrared spectroscopy mineralogy impact melt the Moon

Experimental studies for nuclear chirality in China

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Frontiers of physics 2023年第6期18卷 15-31页

作者：王守宇刘晨亓斌许文政张惠 Shandong Provincial Key laboratory of Optical Astronomy and solar-terrestrial environment School of Space Science and PhysicsInstitute of Space SciencesShandong UniversityWeihai 264209China Weihai Research Institute of Industrial Technology of Shandong University Shandong UniversityWeihai 264209China

In the last decade,chiral symmetry in atomic nuclei has attracted significant attention and become one of the hot topics in current nuclear physics *** paper provides a review of experimental studies for nuclear chirality in *** particular,the experimental setups,chiral mass regions,lifetime measurements,and simultaneous breaking of chirality and other symmetries are discussed in *** studies found a new chiral mass region(A≈80),extended the boundaries of the A≈100 and 130 chiral mass regions,and tested the chiral geometry of^(130)Cs,^(106)Ag,^(80)Br and^(76)Br by lifetime *** addition,simultaneous breaking of chirality and other symmetries have been studied in^(74)As,^(76)Br,^(78)Br,^(80)Br,^(81)Kr and^(131)Ba.

关键词： nuclear chirality lifetime measurements energy spectra electromagnetic transition probabilities