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Science China(Physics,Mechanics & Astronomy) 2015年第6期58卷 103-108页

作者： AN WeiKe DING DaWei CAI AnHui zhou guojun LUO Yun LI JiangHong PENG YongYi College of Mechanical Engineering Hunan Institute of Science and Technology Institute of Physics Chinese Academy of Sciences State Key Laboratory of Powder Metallurgy Central South University School of Physics and Electronics Central South University

Mechanism,condition and characteristics for the formation of the network structure in a group of Zr-Al-Ni-Cu bulk metallic glasses(BMGs) were *** results show that the constituent segregation and/or the symplastic growth would be the mechanisms for the formation of the cell structure in the present Zr-Al-Ni-Cu *** cell structure can be easily obtained for the glass forming alloys whose compositions locate nearby the eutectic *** shorter the distance is from the eutectic point,the larger the cell and the thicker the cell wall of the network structure will *** present investigation would provide useful information for the development of the BMG with the network structure.

关键词： Zr-Al-Ni-Cu bulk metallic glass network structure mechanism characteristics

Structural and thermal sensitivity of Cu-Zr-Ti amorphous alloys to tension

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Science China(Physics,Mechanics & Astronomy) 2013年第8期56卷 1606-1610页

作者： CAI AnHui XIONG Xiang LIU Yong AN WeiKe zhou guojun LUO Yun LI TieLin LI XiaoSong College of Mechanical Engineering Hunan Institute of Science and Technology State Key Laboratory of Powder Metallurgy Central South University

Structural and thermal sensitivity of Cu(60-x)Zr(30+x) Ti 10 (x=0,5,and 10 at%) amorphous alloys to the application of tension was investigated. The structural sensitivity to tension decreases with increasing Cu content. The crystallization enthalpy increases with increasing excess free volume. The characteristic temperatures of the tensile samples can surpass those of the as-cast ones under a critical heating rate which differs in the Cu content. The increase of the excess free volume significantly influences the glass transition and crystallization procedures.

关键词： Cu-based amorphous alloy tension sensitivity

Hendecanuclear [Cu_(6)Gd_(5)] magnetic cooler with high molecular symmetry of D_(3h)

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Chinese Chemical Letters 2021年第2期32卷 838-841页

作者： Weipeng Chen guojun zhou Zhuolun Gou Sen Wang Yuanqi Zhai Tian Han Jurgen Schnack Yanzhen Zheng Shenzhen Research School and Frontier Institute of Science and Technology(FIST) State Key Laboratory for Mechanical Behavior of MaterialsMOE Key Laboratory for Nonequilibrium Synthesis of Condensed MatterXi'an Key Laboratory of Sustainable Energy and Materials Chemistry and School of ScienceXi'an Jiaotong University.Xi'an 710054China School of Chemistry and Chemical Engineering Shaanxi Normal UniversityXi'an 710119China Faculty of Physics Bielefeld UniversityD-33501 BielefeldPO Box 100131Germany

A new family of isostructural 3 d-4 f polymetallic complexes,formulated as [Cu_(6)Ln_(5)(μ_(3)OH)_(9)(C_(4)H_(8)O_(2)N)_(6)(C_(5)H_(4)ON)_(6)(H_(2)O)_(9)]·(ClO_(4))_(6)·(H_(2)O)_(22)(Ln=Pr,1;Nd,2;Sm,3;Eu,4;Gd,5),was successfully isolated through the simple hydrolysis reaction of 2-aminoisobutyric acid,2-hydroxypyridine,Cu(CH_(3)COO)_(2)·H_(2)O,and Ln(ClO_(4))_(3)·6 H_(2)***,the [Cu_(6)Ln_(5)] clusters with high molecular symmetry of D_(3h) are rare examples of2-aminoisobutyric acid-based 3 d-4 f *** successful theoretical modeling of 5 yielded that the Gd-Gd exchange is of order 0.2 K,whereas the Gd-Cu exchange is an order of magnitude *** data collected for comp lex 5 yield a magnetic entropy change(-ΔSm) of 19.6 J kg^(-1) K^(-1)<1 at 3 K and 7 T,which may be attributed to the weak magnetic interactions between the component metal ions.

关键词： Polymetallic complexes Lanthanide elements Hydrothermal reaction Magnetic interactions Magnetic refrigeration

The function of three indigenous plasmids in Mesorhizobium huakuii 2020 and its symbiotic inter-action with Sym pJB5JI of Rhizobium leguminosarum

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Science China(Life Sciences) 2008年第4期51卷 353-361页

作者： YANG ChengYun, LI YouGuo, WEI Li, CHENG guojun & zhou JunChu State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China State Key Laboratory of Agricultural Microbiology Huazhong Agricultural University Wuhan 430070 China

A Mesorhizobium huakuii strain 2020, isolated from a rice-growing field in southern China, contains three indigenous plasmids named p2020a, p2020b and p2020c, respectively. The plasmids were deleted via Tn5-sacB insertion, and two cured derivatives were obtained. Interestingly, the mutant 2020D29 curing of p2020c could significantly enhance the capacity of symbiotic nitrogen fixation. But the mutant 2020D8 curing of p2020b lost the ability to nodulate Astragalus sinicus. Furthermore, the third plasmid p2020a could be hardly eliminated, suggesting that some house-keeping genes necessary for strain growth located on this plasmid. Then the Sym plasmid pJB5JI of R. leguminosarum bv. viciae was transferred into 2020 and its cured derivatives. The pot plant test showed that the ability of competition and symbiotic nitrogen fixation of transconjugant 2020-137 (pJB5JI) was increased evidently in con-trast to 2020. pJB5JI could not restore the ability of 2020D8 to nodulate Astragalus sinicus. 2020D8-8 (pJB5JI) could form ineffective nodules on peas, which implied that the symbiotic plasmid pJB5JI could express its function at the chromosomal background of Mesorhizobium huakuii 2020. The plas-mid stability was checked in transconjugants under free-living and during symbiosis. The results indi-cated that pJB5JI failed to be detected in some nodule isolates. That Km resistance gene could be am-plified from all transconjugants and nodule isolates suggested that pJB5JI was fully or partially inte-grated into the chromosome of recipients.

关键词： Mesorhizobium huakuii indigenous plasmids pJB5JI symbiotic interaction plasmid curing

Unraveling the mechanochemical synthesis and luminescence in MnⅡ-based two-dimensional hybrid perovskite（C4H9NH3）2PbCl4

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Science China Materials 2019年第7期62卷 1013-1022页

作者： guojun zhou Shaoqiang Guo Jing Zhao Quanlin Liu Junying Zhang Zhiguo Xia Beijing Municipal Key Laboratory of New Energy Materials and Technologies School of Materials Sciences and Engineering University of Science and Technology Beijing Beijing 100083 China Key Laboratory of Micro-nano Measurement Manipulation and Physics (Ministry of Education) School of Physics Beihang University Beijing 100191 China Laboratory of Crystal Physics Kirensky Institute of Physics Federal Research Center KSC SB RAS Krasnoyarsk 660036 Russia Siberian Federal University Krasnoyarsk 660041 Russia Department of Physics Far Eastern State Transport University Khabarovsk 680021 Russia

The mechanochemical route is a facile and fast way and has received much attention for developing versatile advanced functional materials. Herein, we reported a mechanochemical synthesis for incorporating divalent manganese ions (Mn^Ⅱ) into a two-dimensional (2D) hybrid perovskite (C4H9NH3)2PbCl4. The mild external stimuli originating from the grinding at room temperature enabled the formation of Mn^Ⅱ-doped 2D hybrid perovskites, and rapidly changed the luminescence characteristics. The photoluminescence analyses show that the violet and orange emissions are attributed to (C4H9NH3)2Pb1-xMnxCl4 band-edge emission and the T1→^6A1 transition of Mn^2+ resulting from an efficient energy transfer process, respectively. Site preference and distribution of the doped Mn^2+ cations on the locations of Pb^2+ were analyzed. The formation energy calculated by the density functional theory (DFT) indicates that the Mn^2+ ions can rapidly enter the crystal lattice due to the unique 2D crystal structure of the hybrid perovskite. Such a case of mechanochemical synthesis for the 2D hybrid perovskite motivates many novel emerging materials and the related applications.

关键词： 2D hybrid perovskite mechanochemical Mn-doping luminescence phosphor

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基于Hadoop的多关键字排序方法研究

计算机工程与应用 2016年第17期52卷 79-83,159页

作者：周国军玉林师范学院数学与信息科学学院广西玉林537000

在单机环境下按多关键字对大数据排序需要较长的执行时间,为了提高按多关键字对大数据排序的效率,根据Hadoop的Map Reduce模型,给出了两种基于Hadoop的多关键字排序方法。方法一在Reduce函数中使用链式基数排序算法按多关键字对大数据... 详细信息

在单机环境下按多关键字对大数据排序需要较长的执行时间,为了提高按多关键字对大数据排序的效率,根据Hadoop的Map Reduce模型,给出了两种基于Hadoop的多关键字排序方法。方法一在Reduce函数中使用链式基数排序算法按多关键字对大数据并行排序,利用多个节点的计算能力提高排序的效率。方法二通过定义组合键和比较器实现了对记录的多个关键字按字节比较,节省了将字节流反序列化为对象的时间。通过实验测试了两种方法的性能,实验结果表明,两种方法均能取得较高的排序效率和较好的可扩展性。

关键词： Hadoop MapReduce模型多关键字排序基数排序

Primary Malignant Giant Cell Tumor of Bone:A Case Report

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Proceedings of Anticancer Research 2021年第4期5卷 23-26页

作者： guojun zhou Sen Li Zhibin Li Qingpeng Deng Peng Wang Xiaowen Sang The First Clinical Medical College of Shaanxi University of Traditional Chinese Medicine Xianyang 712046Shaanxi ProvinceChina Joint Ward Orthopedics HospitalAffiliated Hospital of Shaanxi University of Traditional Chinese MedicineXianyang 712000Shaanxi ProvinceChina

Primary malignant giant cell tumor of bone is clinically rare,lack of specificity,and often ***,related literature about this tumor remains *** case of primary malignant giant cell tumor of bone was diagnosed and treated in our hospital,and the treatment effect was *** was no recurrence or metastasis in 2 years of *** report is as follows.

关键词： Giant cell tumor of bone Primary Malignant Distal femur Tumor resection Hinge knee replacement

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社会学视角下的教育竞争

辽宁教育研究 2007年第11期 18-20页

作者：周国军湖南城建职业技术学院湖南湘潭411101

受社会环境、制度根源及教育系统自身弊病的影响,教育竞争表现出多类型、多层次、带有功利性的目的等特点,也使得本应是人的素质和能力的培养与形成方面的竞争,在教育领域里"异化"为考试能力的竞争,从而导致分数第一、文凭至上的种种异... 详细信息

受社会环境、制度根源及教育系统自身弊病的影响,教育竞争表现出多类型、多层次、带有功利性的目的等特点,也使得本应是人的素质和能力的培养与形成方面的竞争,在教育领域里"异化"为考试能力的竞争,从而导致分数第一、文凭至上的种种异化现象。

关键词：社会学视角教育竞争社会因素

The effect of polarization conditions on P-E loop of tourmaline

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The effect of polarization conditions on P-E loop of tourmal...

退火对冷轧LA91镁锂合金组织与织构的影响

中国晶体学会第六届学术年会暨会员代表大会——多晶（粉晶）衍射分会

作者： guojun zhou Kairen Chen Xinghui Gai You Shan Kun Shen Changchun Zhao School of Science China University of Geosciences

The crystalline phase and chemical composition of three kinds of tourmaline are examined by using X-ray diffraction(XRD) and inductively coupled plasma mass spectrometry(ICP-MS),*** directional slice,the P-E loops of tourmaline(SC-1,XJ-2,HB-1) are measured in different polarization *** is found that the spontaneous polarization along c-axis of tourmaline is larger than that perpendicular to *** on this,the effect of temperature,polarization frequency and dielectric loss on the polarization properties of tourmaline are discussed *** results show that the polarization of tourmaline are composed by the dipole turning-direction polarization and relaxation polarization of thermion and the polarization increases with the rise of temperature,which indicates that the lower electric field and less time are required to reach the saturated polarization *** is indicated that the frequency of electric field is an important factor on the process of polarization in *** addition,the obvious dielectric loss is observed during the polarization process of tourmaline,causing the difficulty for achieving the saturated polarization state.

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金属热处理 2017年第10期42卷 23-26页

作者：周果君唐建国湖南理工学院机械工程学院湖南岳阳414006 中南大学材料科学与工程学院湖南长沙410083

研究了冷轧及轧后热处理对LA91镁锂合金的组织和性能的影响。结果表明,冷轧态LA91合金经240℃×60 min退火后,合金开始再结晶。经过280℃×60 min退火后,合金的再结晶完全,较细的α-Mg熔断成球状,较粗的α-Mg变为竹节状组织,β相呈等轴... 详细信息

研究了冷轧及轧后热处理对LA91镁锂合金的组织和性能的影响。结果表明,冷轧态LA91合金经240℃×60 min退火后,合金开始再结晶。经过280℃×60 min退火后,合金的再结晶完全,较细的α-Mg熔断成球状,较粗的α-Mg变为竹节状组织,β相呈等轴状晶粒;冷轧态LA91合金经退火后,其β相随退火过程不同,{001}立方织构的强度先减弱再增强然后保持不变,{112}织构强度减弱,{111}织构的强度增强。

关键词：镁锂合金冷轧退火显微组织织构