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141.
针对传统垂直切换算法中未能考虑能效这一关键因素,提出了一种能效最优的垂直切换算法,算法核心是移动终端检测并计算来至不同候选网络中的接收信号强度以及各候选小区中的系统容量,以候选小区中每单位能量所能提供的容量作为判决准则切入到最佳网络,同时结合传统的网络因子对多属性判决算法进行能效扩展。仿真结果表明,基于单位能量容量的切换算法较传统的切换算法节省10%左右的能量,扩展的多属性判决算法较传统的切换算法节省7%左右的能量,同时减少了“乒乓效应”,提高了用户的通信体验质量。 相似文献
142.
垂直发射导弹不论在陆地防空系统以及舰上防空系统中得到越来越广泛的应用.而燃气舵是较为传统的垂直转弯方法,在低速时弥补空气舵的舵效不足.而做真实的实验需要点发动机和燃气舵,成本较高,因此在靶试实验前需要做大量的仿真来模拟真实燃气舵烧蚀情况.本文就是依托型号的基础上对燃气舵进行仿真研究,为靶试提供依据. 相似文献
143.
Vertical Phase Separation in Small Molecule:Polymer Blend Organic Thin Film Transistors Can Be Dynamically Controlled
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Kui Zhao Olga Wodo Dingding Ren Hadayat Ullah Khan Muhammad Rizwan Niazi Hanlin Hu Maged Abdelsamie Ruipeng Li Er. Qiang Li Liyang Yu Buyi Yan Marcia M. Payne Jeremy Smith John E. Anthony Thomas D. Anthopoulos Sigurdur T. Thoroddsen Baskar Ganapathysubramanian Aram Amassian 《Advanced functional materials》2016,26(11):1737-1746
Blending of small‐molecule organic semiconductors (OSCs) with amorphous polymers is known to yield high performance organic thin film transistors (OTFTs). Vertical stratification of the OSC and polymer binder into well‐defined layers is crucial in such systems and their vertical order determines whether the coating is compatible with a top and/or a bottom gate OTFT configuration. Here, we investigate the formation of blends prepared via spin‐coating in conditions which yield bilayer and trilayer stratifications. We use a combination of in situ experimental and computational tools to study the competing effects of formulation thermodynamics and process kinetics in mediating the final vertical stratification. It is shown that trilayer stratification (OSC/polymer/OSC) is the thermodynamically favored configuration and that formation of the buried OSC layer can be kinetically inhibited in certain conditions of spin‐coating, resulting in a bilayer stack instead. The analysis reveals here that preferential loss of the OSC, combined with early aggregation of the polymer phase due to rapid drying, inhibit the formation of the buried OSC layer. The fluid dynamics and drying kinetics are then moderated during spin‐coating to promote trilayer stratification with a high quality buried OSC layer which yields unusually high mobility >2 cm2 V?1 s?1 in the bottom‐gate top‐contact configuration. 相似文献
144.
Dr. Wei‐Ming Sun Xiang‐Hui Li Prof. Ying Li Prof. Di Wu Prof. Chun‐Yan Li Prof. Jing‐Hua Chen Prof. Zhi‐Ru Li 《Chemphyschem》2016,17(10):1468-1474
Based on the density functional theory for exchange‐correlation potential, fluorocarbon molecular cages are investigated as building blocks of hyperhalogens. By utilizing C8F7 as a ligand, a series of hyperhalogen anions, that is, M(C8F7)2? (M=Li, Na, and K) and M(C8F7)3? (M=Be, Mg, and Ca), are modeled. Calculations show that all the C8F7 moieties preserve their geometric and electronic integrity in these anions. These anionic molecules possess larger vertical electron detachment energies (5.11–6.45 eV) than that of C8F7?, verifying their hyperhalogen nature. Moreover, it is also revealed that using larger fluorinated cage C10F9 as ligands can bring about hyperhalogen anions with larger vertical electron detachment energies. The stability of these studied anions is determined by their large HOMO–LUMO gaps and positive dissociation energies of predetermined possible fragmentation pathways. It is hoped this study will provide an approach for the construction of new types of hyperhalogens and stimulate more research in superatom chemistry. 相似文献
145.
Reply to: “Comment on Probing the Properties of Polynuclear Superhalogens without Halogen Ligand via ab Initio Calculations: A Case Study on Double‐Bridged [Mg2(CN)5]−1 Anions by Li et al. ”
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Jin‐Feng Li Miao‐Miao Li Dr. Hongcun Bai Yin‐Yin Sun Prof. Jian‐Li Li Dr. Bing Yin 《Chemphyschem》2016,17(18):2947-2947
146.
147.
Vertical excitation energies for DNA and RNA nucleosides are determined with electron structure calculations using the time-dependent density functional theory (TDDFT) method at the B3LYP/6-311++G(d,p) level for nucleoside structures optimized at the same level of theory. The excitation energies and state assignments are verified using B3LYP/aug-cc-pVDZ level calculations. The nature of the first four excited states of the nucleosides are studied and compared with those of isolated bases. The lowest npi* and pipi* transitions in the nucleoside remain localized on the aromatic rings of the base moiety. New low-energy npi* and pisigma* transitions are introduced in the nucleosides as a result of bonding to the ribose and deoxyribose molecules. The effect on the low-lying excited state transitions of the binding to phosphate groups at the 5'- and 3',5'-hydroxyl sites of the uracil ribose nucleoside are also studied. Some implications of these calculations on the de-excitation dynamics of nucleic acids are discussed. 相似文献
148.
The temporal stability on inviscid compressible swirling flow between two concentric cylinders is investigated. First, a linearized differential equation is derived. Two stability criteria are derived for compressible swirling flow by an analytic method analogous to Ludwieg ’s method. A finite-difference numerical method is then used to solve the eigenvalue problem of this differential equation, to get temporal growth rate and to check these stabilitv criteria derived. Finally.The effect of compressibility for stability is disscused. 相似文献
149.
Y. Furukawa S. Noda M. Ishii A. Wakahara A. Sasaki 《Journal of Electronic Materials》1999,28(5):452-456
Vertically stacked layer structure is useful for controlling the size distribution of quantum dots. The dependence of the
size distribution of quantum dots on the stacking numbers is theoretically and experimentally investigated. We show that the
size distribution of quantum dots decreases with increasing the stacking number, and it occurs drastically when the stacking
number is changed from 1 to 2. The quantitative analysis on in-plane strain energy distribution is also performed for the
explanation. 相似文献
150.
垂直分割视场制作合成动态全息图 总被引:1,自引:0,他引:1
从理论上及实验上分析了利用垂直视场分割法制作合成动态全息图的方法。将二步彩虹全息术中的主全息图H1分成若干全息单元,在各单元中分别记录了物体一系列连续变化状态的二维图像,利用该主全息图制作像面全息图H2,从而获得合成动态全息图。该方法用银盐干版记录主全息图H1,节省了大量的曝光时间。 相似文献