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1.
研究了磁性薄膜场电效应的测试方法,RE-TM磁光薄膜的测试样品制备、样品的磁场电效应(霍尔效应和磁阻效应)及其温度特性,实验结果表明,制备的TbFeCo薄膜的补偿点约为-38℃。  相似文献   

2.
研究了以非磁性(Ni0.81Fe0.19)0.66Cr0.34薄膜作为过渡层的坡莫合金Ni0.81Fe0.19薄膜的磁电阻效应和饱和磁场,分析退火处理对样品饱和磁场的影响和经刻蚀后的磁电阻效应膜线的尺寸效应,并建立一个统计模型定性分析了其性能变化的机理,计算结果符合实验。  相似文献   

3.
采用射频溅射法在三组不同溅射条件下制备了FeSiB薄膜。测量了溅射薄膜的磁滞回线 ,并利用HP 41 94A阻抗分析仪 ,在 1~ 40MHz频率范围内研究了样品的巨磁阻抗效应。结果表明 :溅射条件对薄膜磁性能和巨磁阻抗效应影响很大 ,其中氩气压强为 6 65Pa ,磁场感生横向单轴磁各向异性的薄膜具有较好的软磁性能和较大的阻抗变化比值。一定温度下退火能够消除部分应力 ,阻抗变化的灵敏度能提高一倍。另外 ,对巨磁阻抗效应与测量磁场和薄膜易轴的相对位置取向之间的关系也作了讨论  相似文献   

4.
采用射频溅射法在单晶硅衬底上制备了(Fe0.88Zr0.07B0.05)97Cu3薄膜样品。X射线衍射结果表明,未经任何后期处理的沉积态薄膜为非晶态结构。在5kHz~13MHz频率范围内,着重研究了沉积态样品的有效磁导率和巨磁阻抗(GMI)效应的变化特性。研究结果表明,样品具有极好的软磁性能和GMI效应,其矫顽力仅为58A/m,饱和磁化强度约为1.15×106A/m,在13MHz的频率下最大巨磁阻抗比达到17%。并发现有效磁导率比随外磁场的变化,在各向异性场仇。0.4kA/m处出现了峰值,GMI效应也在此磁场的位置处出现峰值。这表明GMI效应与磁场诱导的有效磁导率的变化紧密关联。  相似文献   

5.
阐述了镶嵌纳米复合薄膜的发展、制备、评估及物件。这类薄膜含有镶嵌在介质薄膜中的纳米尺度的金属颗粒或半导体颗粒。作为基础研究,它们可用于研究量子点效应、电子-空穴限域效应、声子限域效应、巨磁阻及非线性光学性能等的研究;作为应用,它们已在光-热转换、恒温系数的电阻膜等获得应用,并将在电双稳开关、光开关及光电器件中获得应用。本文主要介绍了GaAs镶嵌薄膜,同时还介绍了巨磁阻镶嵌薄膜及电双稳薄膜等近年来的实验结果。  相似文献   

6.
采用DC磁控溅射法在玻璃基片上制备了FeCoSiB薄膜和FeCoSiB/Cu/FeCoSiB 三明治膜,并进行磁场退火热处理以消除残余应力和形成磁织构,提高薄膜的应力阻抗效应。薄膜的磁性能采用振动样品磁强计(VSM)进行测试,采用HP4275A 型阻抗分析仪在200kHz~10MHz频率范围内测试薄膜的应力阻抗效应。结果表明,磁场退火热处理可形成感生磁各向异性,改善薄膜的软磁性能、提高薄膜的应力阻抗效应。在温度低于300℃时,随着退火温度的增加,薄膜的应力阻抗效应增大;当退火温度超过300℃时,薄膜的应力阻抗效应随退火温度增加而降低。与Fe CoSiB单层膜相比, FeCoSiB/Cu/FeCoSiB 三明治膜应力阻抗效应较大。10MHz测试频率下,在基片末端位移为450μm时,经300℃热处理的三明治膜达到了8.3%,而单层膜仅有1.86%。当测试频率较高为10和4MHz时,薄膜的应力阻抗效应变化不大,当测试频率下降到低于1MHz时,薄膜的应力阻抗效应显著降低。  相似文献   

7.
铁电薄膜具有反常光生伏打效应,且光伏特性可以通过电场进行调控,在铁电光伏电池、光驱动器、光传感器等方面具有广阔的应用前景.本文对锆钛酸铅、锆钛酸镧铅等铁电薄膜及铁酸铋多铁薄膜的铁电性与光伏特性的关系、界面效应、尺度效应、空间电荷效应等方面及铁电光伏形成机制进行了归纳和分析.今后的研究重点将集中在铁电薄膜电畴驱动光伏形成机制和光伏特性的电、磁场调控机制上.  相似文献   

8.
采用磁控溅射方法在玻璃基片上制备了FeSiB/Cu/FeSiB多层膜,在100kHz~40MHz范围内研究了FeSiB薄膜厚度对FeSiB/Cu/FeSiB多层膜巨磁阻抗效应的影响。当磁场施加在薄膜的纵向时,巨磁阻抗效应随磁场的增加而增加,在某一磁场下达到最大值,然后随磁场的增加而下降到负的巨磁阻抗效应。当FeSiB薄膜的厚度为1.8μm时,在频率3.2MHz、磁场2.4kA/m时,多层膜巨磁阻抗效应达最大值13.5%;在磁场为9.6kA/m时,巨磁阻抗效应为-9.2%。然而,当FeSiB薄膜的厚度为1μm时,多层膜的巨磁阻抗效应在频率40MHz、磁场1.6kA/m时达最大值5.8%。另外,当磁场施加在薄膜的横向时,薄膜表现出负的巨磁阻抗效应。对于膜厚为1.8μm的FeSiB薄膜,在频率5.2MHz、磁场9.6kA/m时,巨磁阻抗效应为-12%。可见巨磁阻抗效应的最大值及负的巨磁阻抗效应与多层膜中磁各向异性轴的取向及FeSiB薄膜的厚度有关。  相似文献   

9.
采用脉冲偏压电弧离子沉积技术在玻璃基片上制备了透明的、具有择优取向的MgO薄膜。针对绝缘性薄膜表面的荷电效应,比较了脉冲偏压作用下鞘层对离子的加速时间(即鞘层的寿命)与脉冲宽度的大小以及偏压鞘层的初始厚度与离子穿越的距离的大小,讨论了不同占空比下偏压鞘层对离子的加速效应。利用X射线衍射及扫描电子显微镜对样品的观察结果表明,由于荷电效应,脉冲偏压幅值为-150 V,占空比在10%~40%的范围内,占空比的变化并不能改变MgO薄膜的微观结构和表面形貌。  相似文献   

10.
对rf溅射法制备的xFe-Al2O3颗粒薄膜,应用X射线衍射仪(XRD)进行了测试和分析,推算了不同样品中Fe粒子的大小和元素面积比.并使用4探针外加磁场法对薄膜的巨磁阻效应进行了分析和讨论.当Fe面积比约为25%时,样品的磁电阻率在1.5T磁场下可达-2.3%.  相似文献   

11.
研究从县级法定计量检定机构的角度出发,阐述了计量比对在确保量值准确可靠、提升技术人员检测水平、验证管理体系运行有效性等方面的实际重要意义,并对基层技术机构开展计量比对现状进行分析,提出建议。  相似文献   

12.
A ternary diagram, representing the solubility of binding solvent (chloroform) in a mixture of ethanol and water, was constructed. For this study, the solvent mixture that gave the best ibuprofen pellets (IPs) was composed of chloroform:ethanol:water at a ratio of 1.5%:8%:90.5%. The suitable agitator speed, temperature, and mixing time were found to be 1500 rpm, 25°C ± 2°C, and 20 min, respectively. In addition, suitable stirring time when the phase partition process of IPs began was 15 min. IPs obtained from these conditions were small and round, approximately 1 mm; surface determination by scanning electron microscopy (SEM) indicated that the IPs were composed of drug microcrystals rearranged on the surface. For the dissolution, IPs showed lower drug release when compared with pure ibuprofen crystal (IC) (f2 analysis). An attempt to modify the dissolution property of IP by incorporating various concentrations of Aerosil and Tween 80 in the binding solvent was made. Microscopic appearance showed that both Aerosil and Tween 80 gave less spherical pellets when compared with the use of binding solvent alone. For both the Aerosil and Tween 80 employed, the results indicated a change in rearrangement of drug microcrystals and a change in crystal habit. However, Tween 80 gave more change of the crystallographic direction of drug microcrystals than Aerosil. In term of dissolution, the results showed that employing Tween 80 at 1.2% gave the highest drug release compared to the use of Aerosil and IC alone (f2 analysis). These pellets had a good flow property, as indicated by Carr's compressibility, flow rate, and angle of repose, and they can be compressed into a tablet, encapsulated by suitable polymer, or pulverized to obtain micronized crystals. In the case of compression into tablets, the dissolution profiles of these tablets compared with those of commercial product meet the USP 24 requirement (Q ≥ 80% at 60 min).  相似文献   

13.
A ternary diagram, representing the solubility of binding solvent (chloroform) in a mixture of ethanol and water, was constructed. For this study, the solvent mixture that gave the best ibuprofen pellets (IPs) was composed of chloroform:ethanol:water at a ratio of 1.5%:8%:90.5%. The suitable agitator speed, temperature, and mixing time were found to be 1500 rpm, 25°C ± 2°C, and 20 min, respectively. In addition, suitable stirring time when the phase partition process of IPs began was 15 min. IPs obtained from these conditions were small and round, approximately 1 mm; surface determination by scanning electron microscopy (SEM) indicated that the IPs were composed of drug microcrystals rearranged on the surface. For the dissolution, IPs showed lower drug release when compared with pure ibuprofen crystal (IC) (f2 analysis). An attempt to modify the dissolution property of IP by incorporating various concentrations of Aerosil and Tween 80 in the binding solvent was made. Microscopic appearance showed that both Aerosil and Tween 80 gave less spherical pellets when compared with the use of binding solvent alone. For both the Aerosil and Tween 80 employed, the results indicated a change in rearrangement of drug microcrystals and a change in crystal habit. However, Tween 80 gave more change of the crystallographic direction of drug microcrystals than Aerosil. In term of dissolution, the results showed that employing Tween 80 at 1.2% gave the highest drug release compared to the use of Aerosil and IC alone (f2 analysis). These pellets had a good flow property, as indicated by Carr's compressibility, flow rate, and angle of repose, and they can be compressed into a tablet, encapsulated by suitable polymer, or pulverized to obtain micronized crystals. In the case of compression into tablets, the dissolution profiles of these tablets compared with those of commercial product meet the USP 24 requirement (Q ≥ 80% at 60 min).  相似文献   

14.
The code for calculating the crown effect rate of hot strip steel Was developed using the effect function method. The effect of the initial crown on the crown of the product in hot strip rolling was investigated. The coefficients of a polynomial of degree six for calculating the base value of initial crown effect rate in 4-high mill were determined and the compensation factors of per unit width rolling force, bending force, work roll crown and draft on the initial crown effect rate were given. The difference between the calculation result by established model and theoretical value obtained by effect function method was 4.88 μm when the strip width was 1.85 m.  相似文献   

15.
钾钠在铸造合金中的作用   总被引:4,自引:0,他引:4  
综述了钾、钠在铸铁、铸钢和铸造有色合金中的应用,并对它们在铸造合金中的作用机理进行了深入分析,最后对扩大钾、钠在铸造合金中的应用,提出了看法。  相似文献   

16.
17.
032 8型氧压机是杭氧 2 0世纪 5 0年代的产品 ,现在已经落后 ,建议两台 0 32 8氧压机串接使用 ,稍加改造 ,可继续发挥作用。  相似文献   

18.
采用一种精确测量形状记忆效应(SME)的方法研究了Cu-26%Zn-4%Al合金800℃淬火后在母相区130,150和170℃时效以及相变热循环过程SME变化的规律。淬火马氏体进入母相区时效初期回复率迅速升高,达到一个最大值以后随时间开始下降,显示出时效过程中马氏体稳定化效应的消除和贝氏体相变发展这两种机制所引起的相反效果。拘束条件下热循环引起回复率的衰减比起自由状态下要缓慢。这可能是应力的存在有利于诱发马氏体相变,使马氏体回复率显著提高所致。  相似文献   

19.
慢性阻塞性肺疾病采用CT诊断效果分析   总被引:1,自引:0,他引:1  
丁建伟 《影像技术》2012,24(4):28-29
目的:探讨CT诊断慢性阻塞性肺疾病的效果方法.选取我院2008年1月至2009年12月46例慢性阻塞性肺疾病患者,将其X线与CT两种诊断的结果进行对比分析.结果:X线与CT两种方法诊断慢性阻塞性肺疾病具有较高的确诊率,实际结果差异性不大.结论:CT技术诊断慢性阻塞性肺疾病有较高的医学价值,值得临床应用.  相似文献   

20.
许立超 《硅谷》2013,(14):94-95
由于医院管理系统信息流通量大加之我国医疗管理系统中还存有不同程度的问题,使得程序混乱、事故频发。本文通过运用RFID技术,阐述其在医疗设备跟踪识别管理系统、病人标识及临床移动护理系统、母婴监护管理平台的开发应用,且应用效果良好。  相似文献   

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