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11.
As they are first optimized for their ion losses,ECRISs are always under a fundamental compromise: having high losses and strong confinement at the same time.To help ECR ion source developers in the design or improvement of existing machines,general comments are presented in a review article being soon published. In this 160 pages contribution,fundamental aspects of ECRISs are presented,with a discussion of electron temperature and confinement and ion confinement.Then,as microwaves play a key role in these machines, a chapter presents major guidelines for microwave launching and coupling to ECR plasma.Moreover,once ECR plasma is created,understanding this plasma is important in ion sourcery;and a section is dedicated to plasma diagnostics with an emphasis on the determination of electron and ion density and temperature by vacuum ultraviolet(VUV)spectroscopy.Another chapter deals with the role of magnetic confinement and presents updated scaling laws.Next chapter presents different types of ECRISs designed according to the main parameters previously described.Finally,some industrial applications of ECRISs and ECR plasmas in general are presented like ion implantation and photon lithography.Some hints taken from this review article are presented in the following article. 相似文献
12.
T. M. Mishonov M. V. Stoev Y. G. Maneva 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(3):533-536
Absorption of Alfvén waves is considered to be the main mechanism of
heating in the solar corona. It is concluded that the sharp increase
of the plasma temperature by two orders of magnitude is related to a
self-induced opacity with respect to Alfvén waves. The maximal
frequency for propagation of Alfvén waves is determined by the
strongly temperature dependent kinematic viscosity. In such a way
the temperature jump is due to absorption of high frequency Alfvén
waves in a narrow layer above the solar surface. It is calculated
the power per unit area dissipated in this layer due to damping of
Alfvén waves that blows up the plasma and gives birth to the
solar wind. A model short wave-length (WKB) evaluation takes into
account the 1/f2 frequency dependence of the transversal magnetic
field and velocity spectral densities. Such spectral densities agree
with old magnetometric data taken by Voyager 1 and recent
theoretical calculations in the framework of Langevin-Burgers MHD.
The presented theory predicts existence of intensive high frequency
MHD Alfvén waves in the cold layer beneath the corona. It is
briefly discussed how this statement can be checked experimentally.
It is demonstrated that the magnitude of the Alfvén waves
generating random noise and the solar wind velocity can be expressed
only in terms of satellite experimental data. It is advocated that
investigation of properties of the solar surface as a random driver by
optical methods is an important task for future solar physics. 相似文献
13.
Recently electron cyclotron resonance (ECR) plasma have been explored for wafer cleaning applications, since it is known to do less damage to silicon surface than conventional plasma. Organic contaminants removal efficiency and plasma radiation damage of the ECR plasma cleaning have been investigated. In oxygen ECR plasma cleaning, the plasma exposure time needed to remove the organic contaminants on the silicon surface down to the detection limit is 40 s, but the one to reach the lowest surface roughness is 10 s. The leakage current level of the MOS capacitor made using the Si substrate exposed to oxygen ECR plasma for 40 s is 8 × 10−9 A. The optimum exposure time determined by considering the contaminants removal efficiency and the plasma radiation damage (or the leakage current level) is 40 s. Organic contaminants seem to be removed through both sputter-off mechanism by oxygen ion bombardment and evaporation mechanism by chemical reactions with excited oxygen atoms. 相似文献
14.
本文描述用硬X射线针孔成象法测量简单磁镜装置中ECR等离子体辐射特性的方法及其结果。这种非破坏性的成象法,直接显示了热电子等离子体的空间分布,一次放电可成一帧清晰的象,且由此可得出二维的等发射强度线。大量结果表明电子环是非轴对称的,并非为一个整环,而是在微波注入口的对面有一个缺口。当微波功率改变时,环也在改变。 相似文献
15.
16.
The 6.4 GHz ECR ion source that was indigenously developed a few years ago has been operating continuously for injecting oxygen
and neon beams to the cyclotron since 1997. VEC-ECR is a single stage high magnetic field ion source provided with a negatively
biased electron repeller placed on the axis, near the injection mirror point. The supply of cold electrons and use of low
mass mixing gas improve the stability of ECR plasma. Very recently, the effect of aluminum oxide coating on the copper plasma
chamber wall has been studied. The plasma chamber wall was coated with aluminum by vacuum evaporation method and then exposed
to oxygen gas to form aluminum oxide. It was noticed that the process substantially shifts the charge state distribution to
the higher charge state with an enhancement of ion current by an order of magnitude. With the aluminized plasma chamber, the
VEC-ECR can now produce 12 μA of O7+, 6.5 μA of Ar12+, 1.5 μA of Kr20+ and 1.0 μA of Xe31+. 相似文献
17.
18.
ECR离子源的等离子体阻抗对其微波传输与阻抗匹配设计至关重要。在中国科学院近代物理研究所现有的2.45 GHz ECR 质子源上,对等离子体阻抗进行了测量。首先用水吸收负载代替等离子体负载测量得到了所用微波窗阻抗,然后根据质子源测量数据,推算得到了等离子体阻抗。实验结果表明,脊波导输出端阻抗与后续负载不完全匹配,等离子体阻抗随微波功率变化呈非线性。这些结果为ECR离子源过渡匹配和微波窗的设计提供了参考依据。Plasma impedance of an ECR ion source is important for microwave transmission and impedance matching design. Plasma impedance was measured indirectly with the 2.45 GHz ECR proton source at the Institute of Modern Physics, Chinese Academy of Sciences. In the test, we got microwave window mpedance by using water absorption load instead of plasma load, and the source plasma impedance was derived from the test data with the 2.45 GHz ECR proton source and microwave window impedance. The experimental results show that ridge waveguide output impedance and the subsequent load does not exactly match, plasma impedance variation is nonlinear with microwave power. The achievedresult is useful in the design of ridged waveguide and microwave window. 相似文献
19.
20.
一台14.5GHz新型高磁场高电荷态ECR离子源 总被引:3,自引:1,他引:2
自行研制成功一台14.5GHz新型高磁场高电荷态电子回旋共振(ECR)离子源.描述了该离子源结构特点、参数优化及其磁场分布,并给出了调试测量结果.该离子源轴向磁镜场在轴线上的最高磁场可达1.5T,六极永磁体在弧腔内表面磁场可达1.0T.经初步调试,可得到07+140eμA,Ar11+185eμA,Xe26+50eμA.所得结果与1998年国际上最好的ECR离子源进行了比较. 相似文献