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Characterization of a broad-energy germanium detector for its use in CJPL

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Nuclear Science and Techniques 2017年第1期28卷 42-48页

作者： Zhi zeng Yu-Hao Mi Ming zeng Hao Ma Qian Yue Jian-Ping Cheng jun-li li Rui Qiu Hui Zhang Key Laboratory of Particle and Radiation Imaging (Ministry of Education) and Department of Engineering Physics Tsinghua University Beijing 100084 China

The broad-energy germanium(BEGe)detector,with the ability of background discrimination using pulse shape discrimination,is a competitive candidate for neutrinoless double beta decay(ovββ)*** this paper,we report our measurements of key parameters for detector modeling in a commercial p-type BEGe ***-like sources are used to investigate energy resolution and linearity of the detector.A cylindrical volume source is used for efficiency *** an assembled device for source positioning and a collimated ^(133)Ba source,the detector is scanned to check its active *** an^(241)Am point-like source,the dead layer thicknesses is measured at about 0.17 mm on the front and 1.18 mm on the *** detector characterization is of importance for BEGe detectors to be used in the ovββ experiments at China JinPing underground Laboratory(CJPL).

关键词： BEGe Characterization Dead layer 0mbb CJPL

师范生职业认同感的效能-价值双维核心模型的构建

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心理发展与教育 2011年第6期27卷 662-669页

作者：王鑫强张大均曾丽红西南大学心理健康教育研究中心、教育科学研究所重庆北碚400715 武夷学院人文与教师教育学院福建武夷山354300

以师范生职业认同感研究的"职业能力"和"职业价值"两大取向为基础,根据其单维评估的不足,将职业效能感和职业价值感指标联合,提出师范生职业认同感的效能—价值双维核心模型,并考察该模型在3所部属师范大学的1237名免费师范生中是否存... 详细信息

以师范生职业认同感研究的"职业能力"和"职业价值"两大取向为基础,根据其单维评估的不足,将职业效能感和职业价值感指标联合,提出师范生职业认同感的效能—价值双维核心模型,并考察该模型在3所部属师范大学的1237名免费师范生中是否存在及其效用。研究表明:(1)模型能有效将免费师范生分组,其中低效能—低价值占31.69%、低效能—高价值占6.63%、高效能—低价值占40.01%、高效能—高价值仅占21.67%,克服了单维评估存在的高估或低估问题;(2)模型在职业认同结果(职业意志感、职业意愿与期望感)、学业满意度、总体生活满意度及未来担忧上的分组效应显著,同时拥有高职业效能感和高职业价值感的免费师范生具有最佳的职业认同感、学业满意度、总体生活满意度和最少的未来担忧。

关键词：免费师范生教师职业认同感职业意志学业满意度心理健康

Single-Particle Properties of Isospin Asymmetric Nuclear Matter

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Chinese Physics Letters 2012年第1期29卷 60-63页

作者： li zeng-Hua ZUO Wei GUO Wen-jun Institute of Modern Physics Department of Nuclear Science and TechnologyFudan UniversityShanghai 200433 Key Laboratory of Applied Ion Beam Physics(Ministry of Education) Fudan UniversityShanghai 200433 Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 College of Science University of Shanghai for Science and TechnologyShanghai 200093

The single-particle potentials in isospin asymmetric nuclear matter is investigated in the framework of the Brueck-ner theory by adopting the realistic Bonn B two-body interaction in combination with a consistent microscopic three-body *** rearrangement contribution induced by the ground state correlations to single-nucleon potentials is calculated in terms of the hole-line expansion of the mass *** the modification of this rearrangement term the symmetry potential is discussed as a function of momentum for several isospin asymme.

关键词： force rearrangement symmetry

Utilization of an H-reversal trajectory of a solar sail for asteroid deflection

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Research in Astronomy and Astrophysics 2011年第10期11卷 1123-1133页

作者： Sheng-Ping Gong jun-Feng li Xiang-Yuan zeng School of Aerospace Tsinghua University Beijing 100084 China

Near Earth Asteroids have a possibility of impacting the Earth and always represent a threat. This paper proposes a way of changing the orbit of the asteroid to avoid an impact. A solar sail evolving in an H-reversal trajectory is utilized for asteroid deflection. Firstly, the dynamics of the solar sail and the characteristics of the H-reversal trajectory are analyzed. Then, the attitude of the solar sail is optimized to guide the sail to impact the target asteroid along an H-reversal trajectory. The impact velocity depends on two important parameters： the minimum solar distance along the trajectory and lightness number of the solar sail. A larger lightness number and a smaller solar distance lead to a higher impact velocity. Finally, the deflection capability of a solar sail impacting the asteroid along the H-reversal trajectory is discussed. The results show that a 10kg solar sail with a lead-time of one year can move Apophis out of a 600-m keyhole area in 2029 to eliminate the possibility of its resonant return in 2036.

关键词： asteroid -- techniques: miscellaneous -- solar sail

Transformation of coccolithophorid Emiliania huxleyi harboring a marine virus(Coccolithoviruses)serine palmitoyltransferase(SPT)gene by electroporation

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Journal of Oceanology and limnology 2021年第2期39卷 693-704页

作者： Weicong CAI Xueting WANG Jinjing SU Jian li jun zeng Guiling li Jingwen liU College of Food and Bioengineering Jimei UniversityXiamen 361021China Fujian Provincial Key Laboratory of Food Microbiology and Enzyme Engineering Xiamen 361021China

Emiliania huxleyi is the most prominent modern coccolithophore,a group of marine unicellular eukaryotes that play a critical role in ocean *** are large double stranded DNA viruses,which is responsible for the demise of large oceanic blooms formed by *** virus(EhVs)acquired a series of enzyme-coding genes predicted to be involved in the sphingolipid biosynthesis by horizontal gene transfer between ***,there is limited experimental validation identifying the functions of these genes in *** transformation of eukaryotic cells is a powerful tool to get an insight into gene functions of the studied *** palmitoyltransferase(SPT)catalyzes the first committed step in de novo sphingolipid biosynthetic ***,a novel vector system for the transformation of *** was *** contained fragments of promoter and terminator sequences of *** endogenic fucoxanthin chlorophyll a/c-binding protein gene“fcp”and harbored EhV-99B1 spt *** resultant recombinant transformation vectors pEhux-I-spt and pEhux-II were co-transferred into *** BOF92 by *** were obtained upon glufosinate-ammonium selection,and confirmed by Southern hybridization,genome PCR,qRT-PCR and Western blot screening of spt gene,which indicated that spt gene was integrated into the nuclear genome and was expressed at the mRNA and protein *** expression of the viral spt gene led to differences in lipid compositions analyzed using thin-layer chromatography(TLC).The results present the genetic transformation system for ***,providing additional genetic resource with potential for exploring basic biological questions such as the virus-host interactions.

关键词： E miliania huxleyi coccolithovirus genetic transformation serine palmitoyltransferase(SPT) total lipid

Microscopic Three-Body Force Effect on Nucleon-Nucleon Cross Sections in Symmetric Nuclear Matter

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Communications in Theoretical Physics 2008年第11期50卷 1219-1224页

作者： ZHANG Hong-Fei ZUO Wei Lombardo Umberto li zeng-Hua li jun-Qing School of Nuclear Science and Technology Lanzhou University Lanzhou 730000 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 730000 China Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China Dipartimento di Fisica Universitk di Catania and INFN-LNS Via S. Sofia 64 1-95123 Catania Italy

We provide a microscopic calculation of neutron-proton and proton-proton cross sections in symmetric nuclear matter at various densities, using the Brueckner Hartree-Fock approximation scheme with the Argonne Va4 potential including the contribution of microscopic three-body force. We investigate separately the effects of three-body force on the effective mass and on the scattering amplitude. In the present calculation, the rearrangement contribution of three-body force is considered, which will reduce the neutron and proton effective mass, and depress the amplitude of cross section. The effect of three body force is shown to be repulsive, especially in high densities and large momenta, which will suppress the cross section markedly.

关键词： nucleon-nucleon cross section nuclear matter three-body force

Three new phenanthrenes from Cremastra appendiculata (***) Makino

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Chinese Chemical Letters 2013年第8期24卷 737-739页

作者： liang liu jun li Ke-Wu zeng Ping li Peng-Fei Tu State Key Laboratory of Natural Medicines China Pharmaceutical University State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking University Health Science Center Medical College Yangzhou University Modern Research Center for Traditional Chinese Medicine Beijing University of Chinese Medicine

Three new phenanthrenes,along with one known phenanthrene,were isolated from the ethanolic extract of the tubers of Cremastra appendiculata（***） *** structures were elucidated on the basis of extensive spectroscopic *** 1-4 were tested for in vitro cytotoxic activities against human lung（A549）,colon（HCT-116）,liver（HepG2）,and breast（MCF-7 and MDA-MB-231） cancer cell lines.

关键词： Phenanthrene Cremastra appendiculata Chemical constituent Cytotoxicity

Enhanced NTRU cryptosystem eliminating decryption failures

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Journal of Systems Engineering and Electronics 2006年第4期17卷 890-895页

作者： Yao jun zeng Guihua Dept. of Electronic Engineering Shanghai Jiaotong Univ. Shanghai 200030 P.R.China

An enhaned NTRU cryptosystem eliminating decryption failures is proposed without using padding schemes and can resist the oracle model andchosen-ciphertext attacks. Because lattice reduction is the main threat to lattice-based cryptosystems, lattice reductionalgorithms are analyzed to evaluate the security of this scheme. Furthermore, the new scheme remains the advantage of high efficiency of original NTRU.

关键词： NTRU cryptosystem polynomial algebra decryption failure lattice reduction.

Nucleon ~3pF_2 Superfluid Pairing Gap in Asymmetry Nuclear Matter

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Communications in Theoretical Physics 2009年第6期51卷 1113-1116页

作者： MI Ai-jun ZUO Wei li zeng-Hua Umberto Lombardo Institute of Modern Physics Chinese Academy of Sciences 730000 Lanzhou China School of Nuclear Science and Technology Lanzhou University 730000 Lanzhou China INFN-LNS and Universit di Catania Catania 1-95123 Italy

The 3 P F2 superfluidity of neutron and proton is investigated in isospin-asymmetric nuclear matter within the Brueckner-Hartree-Fock approach and the BCS theory by adopting the Argonne V14 and the Argonne V18 nucleonnucleon interactions. We find that pairing gaps in the 3PF2 channel predicted by adopting the AV14 interaction are much larger than those by the AV18 interaction. As the isospin-asymmetry increases, the neutron 3 pF2 superfluidity is found to increase rapidly, whereas the proton one turns out to decrease and may even vanish at high enough asymmetries. As a consequence, the neutron 3pF2 superfluidity is much stronger than the proton one at high asymmetries and it predominates over the proton one in dense neutron-rich matter.

关键词： 3pF2 superfluidity asymmetric nuclear matter Brueckner-Hartree-Fock approach BCS theory