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41.
针对高功率板条激光器核心工作器件——板条Nd:YAG晶体的超精密加工开展研究,分析了具有特殊构型的板条Nd:YAG晶体元件的加工性能及工艺难点,提出了一种新的基于合成盘抛光的板条Nd:YAG晶体加工工艺,并对规格为100mm×30mm×3mm的板条Nd:YAG晶体进行了加工实验。实验结果表明,合成盘抛光可以很好地控制元件的塌边现象;通过磨料的优化选择,在合成盘抛光工艺中匹配合适粒度的Al2O3磨料能够实现元件的低缺陷加工,元件下盘后的全反射面平面度达0.217λ(1λ=632.8nm),端面平面度达到0.06λ,表面粗糙度达0.55nm(RMS),端面楔角精度可达2″。 相似文献
42.
鉴于光学零件高陡度凹曲面的抛光是光学加工的一个难题,轮带光学确定性抛光方法是解决此类零件抛光的有效方法之一;提出轮带光学抛光技术的原理和方法。研究了轮带光学抛光方法修形的可行性,采用五轴精密数控机床系统对一块直径Ф80 mm的K9玻璃平面样镜进行了修形试验,经过3次迭代修形使其面形精度均方根误差(RMS)由初始的0109 λ提高到0028 λ,平均每次收敛率达到13。实验结果表明,应用轮带光学抛光技术进行光学镜面修形,面形收敛速度较快,加工精度较高。本实验验证了轮带光学抛光技术的修形能力,为高陡度光学零件的抛光提供了研究基础。 相似文献
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本文以HNO3、NaOH、Fe(NO3)3和SiO2浆料为原料,采用沉淀法制备了1种SiO2/Fe2O3复合磨粒,通过X射线衍射仪(XRD)、飞行时间二次离子质谱仪(TOF-SIMS)和扫描电子显微镜(SEM)对其结构进行表征,结果表明Fe2O3包覆到SiO2的表面,复合粒子具有很好的分散性.用UNIPOL-1502抛光机研究了所制备复合磨粒在镍磷敷镀的硬盘基片中的抛光性能,抛光后硬盘基片的表面粗糙度Ra由抛光前的8.87nm降至3.73nm;抛光后表面形貌的显微镜观测结果表明新制备的复合磨粒表现出较好的抛光性能. 相似文献
46.
J. A. Weima A. M. Zaitsev R. Job G. Kosaca F. Blum G. Grabosch W. R. Fahrner J. Knopp 《Journal of Solid State Electrochemistry》2000,4(8):425-434
Polycrystalline chemical vapor deposition (CVD) diamonds films grown on silicon substrates using the microwave-enhanced CVD
technique were polished using the thermochemical polishing method. The surface morphology of the samples was determined by
optical and scanning electron microscopes before and after polishing. The average surface roughness of the as-grown films
determined by the stylus profilometer yielded 25 μm on the growth side and about 7 μm on the substrate side. These figures
were almost uniform for all the samples investigated. Atom force microscopic measurements performed on the surface to determine
the average surface roughness showed that thermochemical polishing at temperatures between 700 °C and 900 °C reduced the roughness
to about 2.2 nm on both the substrate and growth sides of the films. Measurements done at intermittent stages of polishing
using confocal micro-Raman spectroscopy showed that thermochemical polishing is accompanied by the establishment of non-diamond
carbon phases at 1353 cm−1 and 1453 cm−1 at the initial stage of polishing and 1580 cm−1 at the intermediate stage of polishing. The non-diamond phases vanish after final fine polishing at moderate temperatures
and pressures. Photoluminescence of defect centers determined by an Ar+ laser (λlexct= 514.532 nm) showed that nitrogen-related centers with two zero-phonon lines at 2.156 eV and 1.945 eV and a silicon-related
center with a zero-phonon line at 1.681 eV are the only detectable defects in the samples.
Received: 26 July 1999 / Accepted: 15 November 1999 相似文献
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48.
LBO晶体超光滑表面抛光机理 总被引:1,自引:0,他引:1
胶体SiO2抛光LBO晶体获得无损伤的超光滑表面,结合前人对抛光机理的认识,探讨了超光滑表面抛光的材料去除机理,分析了化学机械抛光中的原子级材料去除机理.在此基础上,对胶体SiO2抛光LBO晶体表面材料去除机理和超光滑表面的形成进行了详细的描述,研究抛光液的pH值与材料去除率和表面粗糙度的关系.LBO晶体超光滑表面抛光的材料去除机理是抛光液与晶体表面的活泼原子层发生化学反应形成过渡的软质层,软质层在磨料和抛光盘的作用下很容易被无损伤的去除.酸性条件下,随抛光液pH值的减小抛光材料的去除率增大;抛光液pH值为4时,获得最好的表面粗糙度. 相似文献
49.
6H-SiC衬底片的表面处理 总被引:1,自引:0,他引:1
相比于蓝宝石,6H-SiC是制作GaN高功率器件更有前途的衬底.本文研究了表面处理如研磨、化学机械抛光对6H-SiC衬底表面特性的影响.用显微镜、原子力显微镜、拉曼光谱、卢瑟福背散射谱表征了衬底表面.结果表明经过两步化学机械抛光后提高了表面质量.经第二步化学机械抛光后的衬底具有优异的表面形貌、高透射率和极小的损伤层,其表面粗糙度RMS是0.12nm.在该衬底上用MOCVD方法长出了高质量的GaN外延膜. 相似文献
50.
Parameters controlling the removal rate of chemical vapor deposition (CVD) diamond films thermochemically polished on transition
metals in a mixed argon-hydrogen atmosphere were investigated. The ambient temperature, the pressure exerted on the diamond
film, the angular velocity of the polishing plate, the frequency and the amplitude of the transverse vibrations were among
the parameters used in the experiments. Temperature measurements showed that the removal rate was increased exponentially
with increasing magnitude of the parameter. An exponential increase in the removal rate was also observed with increasing
pressure and hence with increasing contact between the diamond film and the polishing plate. However, an exponential decrease
in the removal rate was observed with increasing angular velocity of the polishing plate. The removal rate obtained with the
application of transverse vibrations was more than three times that obtained without transverse vibrations. Moreover, the
removal rate was seen to be higher at resonant frequencies. An increase in the removal rate with increasing amplitude of the
transverse vibrations was also observed. Raman measurements carried out on the films to determine the presence of the non-diamond
carbon layer after thermochemical polishing revealed non-diamond Raman lines only for films polished at 1000 °C and 1050 °C
for the temperature range 750–1050 °C.
Received: 27 October 1999 / Accepted: 2 February 2000 相似文献