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61.
M. Ghoranneviss A. Shokouhy M. M. Larijani S. H. Haji Hosseini M. Yari A. Anvari M. Gholipur Shahraki A. H. Sari M. R. Hantehzadeh 《Pramana》2007,68(1):135-140
This work presents the results of a low-energy nitrogen ion implantation of AISI 304 type stainless steel (SS) at a moderate
temperature of about 500°C. The nitrogen ions are extracted from a Kauffman-type ion source at an energy of 30 keV, and ion
current density of 100 μA cm−2. Nitrogen ion concentration of 6 × 1017, 8 × 1017 and 1018 ions cm−2, were selected for our study. The X-ray diffraction results show the formation of CrN polycrystalline phase after nitrogen
bombardment and a change of crystallinity due to the change in nitrogen ion concentration. The secondary ion mass spectrometry
(SIMS) results show the formation of CrN phases too. Corrosion test has shown that corrosion resistance is enhanced by increasing
nitrogen ion concentration.
相似文献
62.
J. V. Pinto M. M. Cruz R. C. da Silva N. Franco A. Casaca E. Alves M. Godinho 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,55(3):253-260
The magnetic and electrical properties of Co-implanted
single crystalline TiO2 rutile are presented. For fluences of
the order of 1017 cm-2 and implantation energy of 150
keV the maximum atomic concentration of cobalt is 13 at% at a depth
of 65 nm from the surface. The as implanted single crystals exhibit
superparamagnetic behaviour attributed to the formation of nanosized
cobalt clusters. After annealing at 1073 K an anisotropic
ferromagnetic behaviour emerges with the easy magnetization axis
lying in the (001) plane of rutile. The ferromagnetic behaviour is
associated with oriented cobalt aggregates. Electrical conductivity
of the implanted samples annealed in vacuum also exhibits
anisotropic behaviour at low temperatures, but no magnetoresistive
effects were detected. 相似文献
63.
伴随着离子束生物技术的广泛应用, 国内许多单位开展了低能离子注入植物种子的实验研究. 其中关于低能离子注入植物种子诱变的物理机理, 集中在离子注入的深度-浓度分布上. 一些单位直接使用纵向非静态(LSS)理论和TRIM程序来计算低能离子注入植物种子的深度-浓度分布, 却发现计算结果与实验测量结果相差甚远. 所以在对植物种子靶材料进行处理和对LSS理论进行修正的基础上, 在二维近似情况下, 用蒙特卡罗方法分别模拟计算了200keV V+和20keV Ti+注入花生和棉花种子的射程分布, 得到了与实验结果较符合的曲线. 在此模型基础上, 计算了同样初始条件和理论计算模型下无法从实验上测量的N+注入植物种子的射程分布, 初步地为低能N+注入植物种子射程分布提供了一种理论计算方法. 相似文献
64.
65.
The rapid scaling of integrated circuit requires further shrinkage of lateral device dimension, which correlates with pillar thickness in vertical structure. This paper investigates the effect of pillar thickness variation on vertical double gate MOSFET (VDGM) fabricated using oblique rotating ion implantation (ORI) method. For this purpose, several scenarios of silicon pillar thickness tsi were evaluated for 20–100 nm channel length. The source region was found to merge at pillar thickness below 75 nm, which results in floating body effect and creates isolated region in the middle of pillar. The vertical devices using ORI method show better performance than those with conventional implantation method for all pillar thickness, due to the elimination of corner effect that degrades the gate control. The presence of isolated depletion region in the middle of pillar at floating body increases parasitic effect for higher drain potential. By further reduction of pillar thickness towards fully depleted feature, the increase in gate-to gate charge coupling improves the performance of ORI-based vertical double gate MOSFET, as evident in near-ideal swing value and lower DIBL, compared to the partially depleted and body-tied device. 相似文献
66.
Y. F. Hsieh Y. C. Hwang J. M. Fu Y. M. Tsou Y. C. Peng L. J. Chen 《Microelectronics Reliability》1999,39(1):15
Ion implantation into contact holes has been widely used to dope the specific contact area and to reduce the contact resistance. In this study, mask edge defects were observed at the edge area of small contact holes with high aspect ratio, which resulted in multiplied dislocations penetrating into Si substrate for more than 0.3 μm after back-end processings. Those dislocations were identified to be Schockley partial dislocations and stair rod dislocations lying on 4 sets of inclined {111}Si planes. 相似文献
67.
氧化物隔离等平面S(z)工艺采用全离子注入工艺代替原始的扩散工艺,使得整个工艺流程更为简化,对于浅结工艺的重复性和均匀性均有较大提高。发射极条和基极条形成自对准,发射极四周靠墙。发射极条宽为3微米时,f_γ>3GHz。该工艺已应用于超高速双极ECL分频器中。 相似文献
68.
本文用卢瑟福背散射和光吸收技术研究了高剂量Ag离子注入SiO_2玻璃以及退火后的状况.吸收光谱测量表明,注入的Ag离子聚集形成了胶态粒子,其等离子共振峰的极大值在400nm处.运用米(Mie)理论和德拜(Doyle)方法,根据测得的等离子共振峰的光宽度,估算出Ag胶态粒子的半径约为18(?). 相似文献
69.
B. Ittermann M. Füllgrabe M. Heemeier F. Kroll F. Mai K. Marbach P. Meier D. Peters G. Welker W. Geithner S. Kappertz S. Wilbert R. Neugart P. Lievens U. Georg M. Keim 《Hyperfine Interactions》2000,129(1-4):423-441
β-active probe nuclei are implanted in nominally undoped ZnSe crystals. β-radiation detected nuclear magnetic resonance (β-NMR)
studies are described for two different probe nuclei, 8Li and 12B. This way, the implantation behavior of two “opposite”dopants, one acceptor (Li) and one donor (B) can be characterized
by the same microscopic technique. Such characterizations are attempted in terms of the structure of intermediate or final
lattice sites, defect charge states, or the kinetics of defect reactions and site changes.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
70.
Mulpuri V. Rao Sadanand M. Gulwadi Phillip E. Thompson Ayub Fathimulla Olaleye A. Aina 《Journal of Electronic Materials》1989,18(2):131-136
Halogen lamp rapid thermal annealing was used to activate 100 keV Si and 50 keV Be implants in In0.53Ga0.47As for doses ranging between 5 × 1012−4 × 1014 cm−2. Anneals were performed at different temperatures and time durations. Close to one hundred percent activation was obtained
for the 4.1 × 1013 cm−2 Si-implant, using an 850° C/5 s anneal. Si in-diffusion was not observed for the rapid thermal annealing temperatures and
times used in this study. For the 5 × 1013 cm−2 Be-implant, a maximum activation of 56% was measured. Be-implant depth profiles matched closely with gaussian profiles predicted
by LSS theory for the 800° C/5 s anneals. Peak carrier concentrations of 1.7 × 1019 and 4 × 1018 cm−3 were achieved for the 4 × 1014 cm−2 Si and Be implants, respectively. For comparison, furnace anneals were also performed for all doses. 相似文献