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1.
Thin film of Ni50Mn35In15 Heusler alloy was prepared on Mg O(001) substrate by epitaxial growth in an ultra-high vacuum(UHV) chamber by a Pulsed Laser Deposition(PLD) method. The epitaxial growth process was monitored by in situ reflection high energy electron diffraction(RHEED) and the structure of the film was checked by ex situ X-ray diffraction(XRD), which indicates that high quality Ni50Mn35In15 single crystal film with a face-centered-cubic(fcc) structure could be stabilized on Mg O(001). Magnetic property measurement was also conducted at various temperatures by using physical property measurement system(PPMS). A significant exchange bias was observed for Ni50Mn35In15 film,and the strength of the exchange bias field(HEB) increases with the decrease of temperature. Such a behavior can be ascribed to the fact that the interfacial spin interaction between ferromagnetic(FM) and antiferromagnetic(AFM) cluster is enhanced with the decrease of temperature.  相似文献   
2.
采用自编的调查问卷,从民族的历史、传统知识、音乐舞蹈、民间工艺、生活习俗礼仪、社会规范、宗教事项、疾病观念、生产技能、心理品质、性别角色和价值观等方面考察了祥云禾甸地区白族对本民族传统文化的知晓度和认知途径.通过对禾甸中学和祥云三中两所中学共260名白族初中学生及其家长的调查研究,发现这一地区的白族家长和学生对本民族文化的知晓度都偏低,且表现出显著的差异性.在文化认知来源上,家长得分均低于其子女得分,且父辈与子代之间存在着中等程度的正相关关系.同时,家长在家庭教育认知来源上存在性别差异;学生则在学校教育和家庭教育上都有差异.通过分析文化认知在民族文化传承中的作用,在此基础上进一步论述了文化认知存在差异的原因及其对民族文化教育的启示.  相似文献   
3.
介绍混合煤气自动调节系统的结构、软件设计以及该系统在调试过程中出现的问题。  相似文献   
4.
引入计量工具对我国的环保投资结构合理性进行检验,结果表明当前的环保投资结构有待优化。分析了我国环保投资结构不合理的原因。结合国情提出了优化我国环保投资结构的建议:转换思路,调整政府环保投资重心;缩小城市环境基础设施建设投资统计口径;加快政府官员绩效考核体系的改革;建立合理的环境保护投资预算体系。  相似文献   
5.
Fossilization     
惠丽菊 《科技信息》2008,(23):263-264
This paper aims at presenting the definition of fossilization and explanation of fossilization so as to provide effective methods to help the second language learners to achieve ultimate success.  相似文献   
6.
The electrocatalytic activity of electrodeposited Ni and Ni–TiO_2 coatings with regard to the alkaline hydrogen evolution reaction(HER) was investigated. The Ni coatings were electrodeposited from an acid chloride bath at different current densities, and their HER activities were examined in a 1.0-mol·L~(-1) KOH medium. The variations in the HER activity of the Ni coatings with changes in surface morphology and composition were examined via the electrochemical dissolution and incorporation of nanoparticles. Electrochemical analysis methods were used to monitor the HER activity of the test electrodes; this activity was confirmed via the quantification of gases that evolved during the analysis. The obtained results demonstrated that the Ni–TiO_2 nanocomposite test electrode exhibited maximum activity toward the alkaline HER. The surface appearance, composition, and the phase structure of all developed coatings were analyzed using scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS), and X-ray diffraction(XRD), respectively. The improvement in the electrocatalytic activity of Ni–TiO_2 nanocomposite coating toward HER was attributed to the variation in surface morphology and increased number of active sites.  相似文献   
7.
We carried out a genome-wide association study of type-2 diabetes (T2D) in individuals of South Asian ancestry. Our discovery set included 5,561 individuals with T2D (cases) and 14,458 controls drawn from studies in London, Pakistan and Singapore. We identified 20 independent SNPs associated with T2D at P < 10(-4) for testing in a replication sample of 13,170 cases and 25,398 controls, also all of South Asian ancestry. In the combined analysis, we identified common genetic variants at six loci (GRB14, ST6GAL1, VPS26A, HMG20A, AP3S2 and HNF4A) newly associated with T2D (P = 4.1 × 10(-8) to P = 1.9 × 10(-11)). SNPs at GRB14 were also associated with insulin sensitivity (P = 5.0 × 10(-4)), and SNPs at ST6GAL1 and HNF4A were also associated with pancreatic beta-cell function (P = 0.02 and P = 0.001, respectively). Our findings provide additional insight into mechanisms underlying T2D and show the potential for new discovery from genetic association studies in South Asians, a population with increased susceptibility to T2D.  相似文献   
8.
用不同浓度的甲醛染毒人宫颈癌Hela细胞、离体小鼠睾丸细胞、昆虫小菜蛾细胞,应用单细胞凝胶电泳技术检测细胞DNA的损伤效应.结果表明:对于Hela细胞和小菜蛾细胞,甲醛在10 μmol/L时可以极显著地诱导DNA断裂(P<0.01);在30 μmol/L时既有断裂也有交联作用(P<0.01),而在50μmol/L时尾部DNA百分比和尾距与阴性对照组无显著差异(P>0.05).对于睾丸细胞,甲醛在10μmol/L、30 μmol/L和50μmol/L时均可导致DNA断裂(P<0.05,P<0.01).该结果提示:甲醛兼具有断裂和交联的作用,可引起多种细胞DNA的损伤.  相似文献   
9.
讨论具有一般平衡项的平均曲率流.如果平衡项有上界,平均曲率流的第一型奇异点是自相似的,而且,如果平衡项的上界足够小,具有此平衡项的凸平均曲率流和一般平均曲率流有相同的性质.  相似文献   
10.
针对不同速度档位和玻璃干湿状态组合工况下刮水器工作时由于摩擦作用引起的刮臂振动、挡风玻璃振动和车内噪声,进行了试验测试.采用时间域、频率域与时频域分析方法,分析噪声的时频特性、影响因素与噪声来源.研究表明,刮水器摩擦噪声可分为换向噪声与刮刷噪声两大类;换向噪声为瞬态冲击噪声,刮刷噪声为宽带并夹杂谐波成分的复杂噪声;换向噪声与刮刷噪声特性受到挡风玻璃干、湿与雨水状态的影响很大,而受速度档位的影响较小;刮刷噪声主要与刮臂侧向振动和法向振动有关,但雨水与半干条件下的刮刷噪声分别来源于驾驶员与副驾驶员侧的刮臂振动.  相似文献   
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