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1.
采用高频感应加热熔融快淬法拉制玻璃包裹的 Fe 基非晶合金细丝,采用温度退火制备纳米晶丝;利用真空镀膜法制作了纵向驱动微型线圈;研究不同退火温度下合成的Fe基合金丝在纵向驱动方式下的巨磁阻抗(GMI)效应.结果表明:对玻璃包裹的Fe基合金非晶丝采用不同退火温度处理,可以不同程度消除材料中的残余应力,提高材料的软磁性能,...  相似文献   

2.
采用Taylor-Ulitovsky方法制备了非晶态玻璃包覆Fe基微丝,合金芯直径为16 μm,玻璃包覆层厚度为3μm.利用X射线衍射和扫描电镜对非晶态玻璃包覆Fe基微丝进行了组织和结构分析,并采用微波网络矢量分析仪测量了试样的微波电磁参数,计算了样品在2~18 GHz的反射率曲线,结果显示在高频时玻璃包覆Fe基非晶微丝阻抗匹配性好,吸收率高.  相似文献   

3.
利用日本同步辐射装置研究了高温高压下Pd40Ni10Cu20P20 块状金属玻璃的非晶-晶化转变. 在10 GPa的压力条件下加热该金属玻璃, 实时观察到了非晶-晶化-非晶的相变规律. 在7 GPa 和同样的温度条件下, Pd40Ni10Cu20P20金属玻璃仅存在非晶-晶化这样不可逆相变. 将该金属玻璃在7 GPa的压力条件下加热到熔化温度, 然后淬火到室温, 发现淬火后获得的晶化相与加热金属玻璃得到的 晶化相完全不同. 表明该金属玻璃在不同的压力条件下存在着不同的晶化机制.  相似文献   

4.
用氢氟酸去掉Co69.20Fe4.16Si12.35B10.77Cr3.42Mo0.1非晶玻璃包裹丝的玻璃层,获得了高纯度的Co基非晶丝,再对非晶细丝在空气或氢气保护中进行了退火处理,研究了退火过程中退火温度和退火时间对Co基非晶丝巨磁阻抗效应(GMI)的影响.研究发现,随着退火温度升高和退火时间加长,Co基非晶丝巨磁阻抗表现出非单调且非对称的变化,灵敏度随着退火温度的升高和退火时间的加长表现为先增大后减小的行为.在退火温度为673K,退火时间为9h的条件下,磁阻抗的灵敏度最高,可达227%.分析指出氧化层和纳米晶芯层的耦合相互作用可能是Co基非晶丝软磁性能得到改善的主要原因.  相似文献   

5.
为了制作出具有多种孔径和锥度的低成本玻璃微喷嘴,基于玻璃热变形锻制工艺,设计并制作了玻璃微喷嘴锻制仪.锻制仪主要由温度可调的加热源和可编程运动控制部分构成.首先,通过控制玻璃材料的变形长度及各部分的加热时间,得到具有不同孔径和锥度的微喷嘴.然后,以孔径200μm、内流道收缩角度15°的玻璃微喷嘴为例,在液体微喷射系统平台上进行液-液相喷射实验.实验结果表明:在1~10Hz驱动频率范围内,喷射过程中微喷嘴端口没有挂滴,喷出液滴直径约为160μm.利用玻璃微喷嘴锻制仪所制作的微喷嘴能够满足非接触式点样法制备生物芯片微阵列所要求的单滴性和稳定性.  相似文献   

6.
衍射法测量细丝直径的研究   总被引:7,自引:0,他引:7  
就几种影响因素从理论和实验上对激光衍射法测量细丝直径进行了研究,结果表明利用简单测量装置和采用一些简单的数字信号处理技术后,即可对50~120μm范围的细丝直径进行较高精度的测量,达到1%的重复性精度。  相似文献   

7.
作为新兴非晶材料的金属玻璃由于其优异的力学、物理以及化学性能而被广泛研究.玻璃形成能力一直是制约着非晶材料发展的重要问题,为了设计出具有良好玻璃形成能力的非晶材料,对非晶材料的玻璃形成能力已经有大量的研究.研究表明单一的影响因素不足以全面解释非晶材料的玻璃形成能力,即玻璃形成能力是由多种因素共同影响的.另一方面,由于非晶材料具有复杂且无序的结构,传统的方法难以全面、清晰地理解非晶材料的结构与本质.机器学习这一新的研究范式为解决非晶材料领域的关键瓶颈问题提供了新的途径和契机.本文首先简单介绍了一些机器学习算法,如支持向量机、人工神经网络和K均值聚类.随后介绍了机器学习在非晶材料中的应用,包括非晶结构分类、非晶结构-性能关联和非晶宏观性质的预测,并提出了基于机器学习方法在未来非晶研究中的应用前景,包括非晶数据库的建立、高通量计算方法的发展和机器学习势函数的发展.  相似文献   

8.
为了简化用于微流体脉冲惯性驱动-控制的T型玻璃微喷嘴的制作工艺,设计制作了重力式玻璃微喷嘴制作仪、微孔制作仪。研究了拉力、线圈温度、延时时间、线圈宽度对拉制工艺,加热时间、进给量对锻制工艺,加热面积对微孔制作工艺的影响规律。制作了微喷嘴、微管道、玻璃微孔等基本微流体器件并以紫外线(UV)光学胶水密封组合,设计制作了T型玻璃微喷嘴。设计了拉锻集成式玻璃微流体器件制作设备,其拉制工艺延时控制结构比非延时控制结构制作的微喷嘴锥长可减小3.5 mm。微孔制作仪可在玻璃毛细管侧壁开制400μm圆形微孔。制作了序列玉米胚芽油海藻酸钠水油(W-O)乳液和500μm左右的单、双颗玉米胚芽油微胶囊,其粒径均匀、形态良好。结果表明,基于冷热加工工艺及组合工艺可以制作结构简单、生物化学性能和光学性能良好的T型组合玻璃微流体器件,基于脉冲惯性驱动可以产生多相流体脉冲流动及微喷射。  相似文献   

9.
纵向驱动纳米微晶玻璃包裹丝的巨磁阻抗效应   总被引:5,自引:2,他引:3  
采用高频感应加热熔融拉引法制备Fe73.0Cu1.0Nb1.5V2.0Si13.5B9.0 非晶玻璃包裹细丝,经适当温度退火处理得到纳米微晶丝。首次研究了样品在纵向驱动方式下的巨磁阻抗效应,发现T=570℃下退火得到的样品,在驱动电流频率f=300kHz时其最大磁阻抗变化可达1020%.  相似文献   

10.
采用高频感应加热熔融拉引法制备Fe73.5Cu1Nb3Si13.5B9玻璃包裹合金非晶丝,其中金属芯的直径为16~50 μm,经570 ℃退火处理得到具有最佳软磁性能的玻璃包裹纳米晶丝.研究其巨磁阻抗效应,发现随金属芯直径的增大,丝的磁阻抗变化先增大后减小,在30 μm时具有最大磁阻抗变化为251%.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
19.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

20.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

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