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41.
粉末贮氢合金作为一种功能材料在许多领域已有广泛应用。而薄膜贮氢合金是80年代国外新开发的功能材料。目前国外制备薄膜贮氢合金的方法主要有热蒸发法(包括闪蒸)和磁控溅射法。最近我们采用一种新颖的制备方法——离子束溅射法研制非晶态、晶态Ti-Ni薄膜合金。 相似文献
42.
An open quantum battery (QB) model of a single qubit system charging in a coherent auxiliary bath (CAB) consisting of a series of independent coherent ancillae is considered. According to the collision charging protocol we derive a quantum master equation and obtain the analytical solution of QB in a steady state. We find that the full charging capacity (or the maximal extractable work (MEW)) of QB, in the weak QB-ancilla coupling limit, is positively correlated with the coherence magnitude of ancilla. Combining with the numerical simulations we compare with the charging properties of QB at finite coupling strength, such as the MEW, average charging power and the charging efficiency, when considering the bath to be a thermal auxiliary bath (TAB) and a CAB, respectively. We find that when the QB with CAB, in the weak coupling regime, is in fully charging, both its capacity and charging efficiency can go beyond its classical counterpart, and they increase with the increase of coherence magnitude of ancilla. In addition, the MEW of QB in the regime of relative strong coupling and strong coherent magnitude shows the oscillatory behavior with the charging time increasing, and the first peak value can even be larger than the full charging MEW of QB. This also leads to a much larger average charging power than that of QB with TAB in a short-time charging process. These features suggest that with the help of quantum coherence of CAB it becomes feasible to switch the charging schemes between the long-time slow charging protocol with large capacity and high efficiency and the short-time rapid charging protocol with highly charging power only by adjusting the coupling strength of QB-ancilla. This work clearly demonstrates that the quantum coherence of bath can not only serve as the role of "fuel" of QB to be utilized to improve the QB's charging performance but also provide an alternative way to integrate the different charging protocols into a single QB. 相似文献
43.
半导体硅上电沉积Cu/Co层状薄膜 总被引:2,自引:0,他引:2
由磁性层和非磁性层组成的人工调制层状结构多层膜,其物性和磁性都表现出与其它结构的多层膜显著不同的特点,如巨磁阻效应[’,‘l、易磁性方向的改变等”].其性能的研究不但在磁性理论上具有重大意义,而且有望应用于高性能的磁阻敏感设备及提高磁记录密度等.因而近年来有关这方面的研究越来越引起人们的重视.目前,磁性多层膜的制备主要采用气相沉积、磁控溅射、分子束外延等真空技术.由于电沉积技术具有设备简单、操作方便等特点而成为制备多层膜的颇具活力的工艺.CO/Cll多层膜在C。层厚度较薄时具有较高室温巨磁阻(GMR)… 相似文献
44.
近年来,越来越多的实验表明,很多轻奇特核结构中都有核心激发成分。本研究以丰中子晕核11Be为例,介绍核心激发成分的实验和理论研究进展,重点阐述核心激发成分对直接核反应微分截面的影响。实验上,1n移除反应及11Be(p,d)和10Be(d,p)转移反应是测量11Be核心激发成分比例的典型实验类型。理论上,发展了能够包括11Be核心激发成分的Faddeev AGS方法,XDWBA方法以及XCDCC方法。加入核心激发成分后,这些模型的计算结果可以更加合理地描述11Be在各种靶上的弹性散射和碎裂微分截面。通过对比是否包含核心激发成分的计算结果,发现其影响主要体现在弹散微分截面的大质心系角度,以及(p,d)转移反应角分布的小质心系角度。另外,对Ex=0:5s3 MeV的激发能区的碎裂反应,核心激发的影响不可忽略;对Ex=3s5:5 MeV的碎裂反应,核心激发的贡献非常重要。It was found that many light exotic nuclei have the core-excitation components. In this paper, taking one-neutron halo nucleus 11Be for example, the experimental and theoretical research progress, as well as the influences on the direct nuclear reaction differential cross sections of this exotic component were reviewed. The 1n removal, 11Be(p, d) and 10Be(d, p) transfer reactions are typical experimental methods to investigate this component. The Faddeev AGS, the XDWBA, and the XCDCC methods are developed to include this constituent in various theoretical models. With the core-excitation component, the calculated results can more reasonably describe the elastic scattering and breakup differential cross sections of 11Be impinging on various targets. Comparing the full XCDCC calculation with that omitting core-excitation effect, we found that this component mainly affects the elastic scattering differential cross sections at large center-of-mass angles, and the (p, d) transfer reaction angular distributions at small center-of-mass angles. In addition, its effect is non-negligible for the breakup reaction within the excitation energy interval of Ex = 0:5~3 MeV, and is remarkable for Ex =3 5:5 MeV. 相似文献
45.
46.
在略高溫度下,通过氯化锂和金属钠在氫气氛中的反应,得到了氢化锂和氯化钠的混合物。用通常的Schlesinger法将得到的混合物用于合成氢化铝锂。反应的副产物是氯化锂和氯化钠的混合物,可用不同方法将其分离,所得氯化锂用于再循环。 相似文献
47.
48.
储氢材料新合成方法的研究(Ⅱ)——置换—扩散法合成Mg_2Ni 总被引:8,自引:0,他引:8
本文用置换-扩散法合成了储氢材料Mg_2Ni.它是在二甲基甲酰胺中,用金属镁锉屑去置换溶液中化合态的镍(NiCl_2),使镍接镀在镁上.然后在温度500—580℃、氩气氛下扩散2-3小时.所得的Mg_2Ni有较好的物理和化学性能,特别是氢化物分解温度有明显的降低. 相似文献
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50.
从教学法規点来看权限理论是中学数学课的最困难的章节之一。涉及到的概念的新奇和抽象常常使学生仅仅形式地掌握这一理论,看不出与他們在学校里所学的东西的联系和与他們周围生活中的事物的联系。这些不能容忍的缺点由于在中学課程中引进了高等数学因素就变得特別危险了,要知道,不真正掌握极限概念就不可能理解什么是导数或积分(虽然积分还沒有列入中学大綱,但是希望这次改革不会半途而 相似文献