全文获取类型
收费全文 | 2884篇 |
免费 | 281篇 |
国内免费 | 516篇 |
专业分类
化学 | 1826篇 |
晶体学 | 70篇 |
力学 | 382篇 |
综合类 | 12篇 |
数学 | 311篇 |
物理学 | 1080篇 |
出版年
2024年 | 12篇 |
2023年 | 46篇 |
2022年 | 68篇 |
2021年 | 73篇 |
2020年 | 96篇 |
2019年 | 78篇 |
2018年 | 72篇 |
2017年 | 120篇 |
2016年 | 124篇 |
2015年 | 121篇 |
2014年 | 169篇 |
2013年 | 194篇 |
2012年 | 166篇 |
2011年 | 247篇 |
2010年 | 185篇 |
2009年 | 210篇 |
2008年 | 189篇 |
2007年 | 190篇 |
2006年 | 166篇 |
2005年 | 141篇 |
2004年 | 129篇 |
2003年 | 120篇 |
2002年 | 82篇 |
2001年 | 81篇 |
2000年 | 84篇 |
1999年 | 53篇 |
1998年 | 64篇 |
1997年 | 52篇 |
1996年 | 37篇 |
1995年 | 35篇 |
1994年 | 45篇 |
1993年 | 37篇 |
1992年 | 24篇 |
1991年 | 17篇 |
1990年 | 23篇 |
1989年 | 19篇 |
1988年 | 16篇 |
1987年 | 18篇 |
1986年 | 12篇 |
1985年 | 14篇 |
1984年 | 4篇 |
1983年 | 7篇 |
1982年 | 14篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1979年 | 5篇 |
1978年 | 6篇 |
1977年 | 2篇 |
1973年 | 1篇 |
排序方式: 共有3681条查询结果,搜索用时 14 毫秒
991.
《Current Applied Physics》2020,20(10):1163-1170
Biomimetic inspiration from the moth-eye structure has led to many studies combining nanoimprint lithography (NIL) to realize low cost and large area anti-reflection (AR) coatings. However, the scope of application is severely limited by poor mechanical performance due to the intrinsic properties of the coating materials and the nanosized patterns. In this work, we demonstrate a moth-eye structured epoxy-siloxane molecular hybrid (ME-ESMH) fabricated using single UV-based NIL (UV-NIL) on a colorless polyimide (CPI), to be utilized as a flexible cover window (FCW) for foldable displays. Low reflection, a superhydrophobicity and good inward foldability were achieved, together with excellent thermal and chemical resistance. Furthermore, in situ uniaxial compression tests revealed that the fabricated structure can be elastically deformed and nearly restored to its original shape even after a large degree of compression. Our findings provide an easy-to-integrate solution for flexible hard coatings with superhydrophobic and AR properties, applicable to foldable optoelectronics. 相似文献
992.
A. V. Stankevich A. A. Muravsky A. A. Murauski V. E. Agabekov 《Molecular Crystals and Liquid Crystals》2018,669(1):106-113
Were formed anisotropic thin films of oligo(p-phenylene vinylene) dye on the surface of rubbed nylon during rod-coating from chloroform and chlorobenzene solutions. The order parameter and alignment direction of films depend on the solvent type and the temperature. On coating from chloroform solution molecules in the dye film align perpendicular and parallel to rubbing direction at temperatures below 40?°C and above 60?°C, correspondingly. Homogeneously oriented anisotropic films with a dichroic ratio of more than 25 were obtained. 相似文献
993.
毛细管电泳柱及微流控芯片通道涂层的发展 总被引:2,自引:0,他引:2
综述了用于毛细管电泳柱和微流控芯片通道的涂层材料和涂层技术的发展状况,以及涂层对分离效果和分离结果重现性的影响。将涂层材料按照动态和静态分类,静态涂层又分别按照均聚物、共聚物、杂环类等进行讨论;综述了交联反应法、溶胶-凝胶法、辐照法、化学沉积法等涂层的制备方法。对毛细管电泳柱和微流控芯片通道的改良具有一定的参考价值。 相似文献
994.
995.
导电聚苯胺的合成、结构、性能和应用 总被引:41,自引:0,他引:41
概述了中国科学院长春应用化学研究所对导电聚苯胺合成、结构、性能和应用的研究.从合成可溶性的聚苯胺入手,阐明了聚苯胺的若干基本化学和结构问题,提出并证明了掺杂态聚苯胺的结构模型和掺杂机理;除了质子酸掺杂外,发现了聚苯胺的碘氧化掺杂、光助氧化掺杂和K+注入还原掺杂;开发了分别以环氧树脂和聚氨酯为载体的聚苯胺防腐涂料;运用掺杂剂诱导的溶解性,通过合成带聚乙二醇链的膦酸掺杂剂,实现了导电态聚苯胺的水体系加工.其中的聚苯胺树脂及防腐涂料的生产技术,已经完成中试,正在走向产业化. 相似文献
996.
997.
以6-(1-萘氧基甲酰胺基)己酸(CNH)偶联牛血清白蛋白(BSA)作为免疫原(CNH-BSA)制备高特异性抗体,分别以CNH、4-(1-萘氧基甲酰胺基)丁酸(CNB)、3-(1-萘氧基甲酰胺基)丙酸(CNA)偶联卵清蛋白(OVA)得到包被抗原(CNH-OVA,CNB-OVA,CNA-OVA),以上述抗体及包被原作为核心材料,研究了同源包被与异源包被模式及ELISA各影响因素对检测灵敏度的影响,建立了甲萘威异源间接竞争酶联免疫法,并考察了此方法对测定大米及土壤中甲萘威残留的适用性。结果表明:以CNA-OVA异源包被的间接竞争ELISA法具有较高的灵敏度,IC50为(10.51±0.11)μg·L-1,该方法的检测范围为2.07~47.30μg·L-1(以IC20~IC80为标准)。以0.5,1.0,2.0,4.0 mg·kg-1作为加标浓度,甲萘威在大米中的加标回收率为92.3%~111.6%,土壤中的加标回收率为85.3%~103.2%,相对标准偏差均在10%以内。与HPLC法的比对验证结果表明,ELISA和HPLC两种方法的分析结果无显著性差异(P0.05)。 相似文献
998.
J. I. RAMOS 《国际流体数值方法杂志》1996,22(10):961-978
Asymptotic methods are employed to derive the leading-order equations which govern the fluid dynamics of time-dependent, incompressible, planar liquid sheets at low Reynolds numbers using as small parameter the slenderness ratio. Analytical and numerical solutions of relevance to both steady film casting processes and plane stagnation flows are obtained with the leading-order equations. It is shown that for steady film casting processes the model which accounts for both gravity and low-Reynolds-number effects predicts thicker and slower planar liquid sheets than those which neglect a surface curvature term or assume that Reynolds number is zero, because the neglect of the curvature term and the assumption of zero Reynolds number are not justified at high take-up velocities owing to the large velocity gradients that occur at the take-up point. It is also shown that for Reynolds number/Froude number ratios larger than one, models which neglect the surface curvature or assume a zero Reynolds number predict velocity profiles which are either concave or exhibit an inflection point, whereas the model which accounts for both curvature and low-Reynolds-number effects predicts convex velocity profiles. For plane stagnation flows it is shown that models which account for both low-Reynolds-number and curvature effects predict nearly identical results to those of models which assume zero Reynolds number. These two models also predict a faster thickening of the planar liquid sheet than models which account for low- Reynolds-number effects but neglect the surface curvature. This curvature term is very large near the stagnation point and cannot be neglected there. It is also shown that the thickening of the sheet occurs closer to the stagnation point as the Reynolds number/Froude number ratio is increased, i.e. as the magnitude of the gravitational acceleration is increased. In addition it is shown that large surface tension introduces a third-order spatial derivative in the axial momentum equation at leading order. 相似文献
999.
Metallic nanoparticles are deposited on multilayers of an unsaturated phospholipid to form a planar nano-composite material. At temperatures near or above the main transition of the lipid, the organic layers exhibit a high degree of mobility and allow for a significant rearrangement of the metallic particles. Originally after deposition, the inter-particle distances correspond to the average bilayer thickness of the given phospholipid. After annealing of the composite structure in the presence of moisture, the spacing between the particles is significantly reduced, associated with an interdigitation of aliphatic chains in the hydrophobic region. This phenomenon is still observed after UV irradiation of the unsaturated hydrocarbon chains. 相似文献