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1.
多辊轧机冷轧技术在靶材料制备中的应用   总被引:9,自引:1,他引:9       下载免费PDF全文
 叙述了多辊轧机轧制金属薄膜原理,以Ti膜制备为例,借助多辊轧机冷轧技术进行1.5 μm厚钛薄带的制备工艺研究。对薄膜的特性测试结果表明:工作辊的表面粗糙度对于轧制薄膜的表面粗糙度的影响很大,降低工作辊表面的粗糙度可以得到粗糙度为25.2 nm的金属薄膜。  相似文献   

2.
Integrable Rosochatius deformations of finite-dimensional integrable systems are generalized to the soliton hierarchy with self-consistent sources. The integrable Rosochatius deformations of the Kaup-Newell hierarchy with self-consistent sources, of the TD hierarchy with self-consistent sources, and of the Jaulent-Miodek hierarchy with self-consistent sources, together with their Lax representations are presented.  相似文献   

3.
给出了利用叠片法测量“闪光二号”加速器高功率离子束能谱的基本原理及初步实验结果. 采用Ziegler的拟合公式编制程序计算了不同能量质子和碳离子穿过不同厚度Mylar膜后的能 量损失情况.在偏压法拉第筒阵列各个法拉第筒的准直孔前分别覆盖0—6μm厚的Mylar膜, 根据不同膜厚对应的信号衰减情况(叠片法),得到了高功率离子束的离子能谱,离子的最高 能量>440keV,平均能量约为270keV,能量为200—300keV之间的离子数目最多,碳离子数和 90keV以下的质子所占总离子数的组分不多于32%.所测量离子能谱和离子数目随时间的分布 关系与二极管的电压和电流符合也较好.还将叠片法的测量结果与利用磁谱仪和采用飞行时 间法等的测量结果进行了比较,三种方法所得的测量结果基本一致. 关键词: 高功率离子束 离子能谱 法拉第筒 叠片法 能量损失  相似文献   

4.
星载高分辨率超光谱成像仪分光方式的选择   总被引:3,自引:0,他引:3  
从多个方面分析了棱镜和光栅色散分光的优缺点,分析结果表明棱镜更适于星载高分辨率超光谱成像仪的分光。在透过率方面,棱镜光谱仪透过率高达95.24%(VNIR),而光栅的衍射效率仅为60%~70%。在杂散光方面,棱镜光谱仪的杂散光可达10-4,而光栅的杂散光为10-2。在0.4 -2.5 范围,棱镜光谱仪相对光栅光谱仪有优越性。在色散线性方面,光栅光谱仪基本线性,棱镜光谱仪的短波非线性问题可通过复合棱镜进行补偿。可靠性方面,棱镜光谱仪较光栅光谱仪有优势;在光谱带宽和成本方面,棱镜光谱仪与光栅光谱仪基本接近。  相似文献   

5.
Predictions of nonlinear theories on dynamics of new phase formation have been examined for the hydration of calcium silicates with light water and heavy water. In the case of hydration with light water, reasonable agreement has been observed with dynamical scaling hypothesis with a new measure of the characteristic length. The characteristic length does not follow a power law relation with time. Hydrating mass is found to be mass fractal throughout hydration, with mass fractal dimension increasing with time. But, in the case of hydration with heavy water, no agreement has been observed with the scaling hypothesis. Hydrating mass undergoes transition from mass fractal to surface fractal and finally again to mass fractal. The qualitative features of the kinetics of hydration, as measured in small-angle scattering experiments, are strikingly different for hydration with light water and heavy water.  相似文献   

6.
带有损耗的光波导微环谐振器在实现光速控制时存在输出脉冲能量损耗大、脉冲形状畸变严重等问题。基于带有增益和带有损耗的微环谐振器的传输特性之间的对称性,计算分析了单微环谐振器的透射率、群折射率和群速度色散等特性,分析了增益和损耗对微环谐振器输出特性影响的机制。计算了带有增益的微环谐振器的光速控制行为,并与带有损耗的微环谐振器进行对比。结果显示,带有增益的微环谐振器输出脉冲不分裂且有较大的输出强度。脉冲延迟量和超前量比损耗系统大,可用于光速控制,克服了微环带有损耗时产生的光强损耗和脉冲畸变。  相似文献   

7.
马廷锋  张超  江小宁  冯冠平 《中国物理 B》2011,20(4):47701-047701
Quartz crystal resonators (QCRs) with circular electrodes have been widely used for various liquid and gas sensing applications. In this work,quartz crystal resonators with elliptical electrodes were studied and tested for liquid property measurement. Mindlin’s theory was used to optimize the dimension and geometry of the electrodes and a 5-MHz QCR with minimum series resistance and without any spurious modes was obtained. A series of AT-cut QCRs with elliptical electrodes of different sizes were fabricated and their sensing performances were compared to devices with circular electrodes. The experimental result shows that the device with elliptical electrodes can obtain lower resonance impedance and a higher Q factor,which results in a better loading capability. Even though the sensitivities of devices with elliptical and circular electrodes are found to be similar,the sensor with elliptical electrodes has much higher resolution due to a better frequency stability. The study indicates that the performance of QCRs with elliptical electrodes is superior to that of traditional QCRs with circular electrodes.  相似文献   

8.
Summary The dynamical evolution of star clusters with a initial population of binaries strongly depends on the parameters of the bounded pairs. We performed computational simulation with directN-body codes, on models withN=300 objects, with initial fraction of 20% of binaries with the same orbital semi-axis and with a Salpeter mass spectrum. The results are compared with previous analysis on similar equal-mass star models. The calculation points out that binaries with different mass companions determine an enhanced and sudden expansion of the system with neither core collapse nor central mass segregation. Paper presented at the 2° Convegno Nazionale di Fisica Cosmica, held at L'Aquila, 29 May – 2 June 1984.  相似文献   

9.
We present results from a novel variational method for the study of beam propagation in a Kerr medium with nonlinear absorption. This new method combines the variational method and a nonlinear absorption equation and gives a concise expression for the combination. The results obtained with this method show good quantitative agreement with numerical solutions obtained with the finite-difference method. It is shown that the variational method takes much less time than a numerical simulation with the finite-difference method for analysis of beam propagation in a thick medium with nonlinear absorption and nonlinear refraction. The new method makes detailed analysis of beam propagation in a Kerr medium with nonlinear absorption very simple and fast.  相似文献   

10.
针对铜铝复合管(ACC管)在空调用翅片管换热器中替代铜管应用进行了试验研究。分别对Ф7.94mm型管的全铜管、过冷段铜铝复合管、全铜铝复合管三种换热器进行了性能比较和成本分析。研究结果表明,在风速和风量不变的情况下,过冷段铜铝复合管换热器能力为8634.22W,高于全铜铝复合管的换热器的8389.36W,低于全铜管换热器的8989.07W。制冷剂侧能力测试中,过冷段铜铝复合管换热器平均值为8.885kW,与全铜铝复合管换热器平均值8.775kW相比高1.24%,与全铜管换热器平均值9.101kW相比低2.37%,与能力测试结果基本一致。与原换热器铜管相比,在相同条件下,铜铝复合管可以降低管材成本29.5%。综上所述,过冷段采用铜铝复合管的换热器能够取代铜管换热器应用在空调中,在不影响其换热性能的基础上,降低成本效果明显。  相似文献   

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