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121.
由于在微电子器件制造,成像系统及太阳能电池等领域里具有广阔的应用前景,激光诱导化学及电化学沉积金属的研究,最近几年引起了极大兴趣[1-3],例如Zahavi[4]报道了Pd,Au,Ni-Pd在氩离子激光作用下可以不加偏压实现在半导体Si,InPGaAs上的无掩膜选择性沉积,金属沉积只发生在光照部位.大多数研究工作是围绕应用技术而开展的,理论研究,尤其是光电化学方面的研究尚十分欠缺.我们认为对于普通电镀液中的激光诱导电沉积来讲,既使不需外加偏压,沉积过程也必然伴随着溶液中金属离子与半导体能带之间的电荷传递,因此可以通… 相似文献
122.
Zhen-Qian Zhang Hong Li Juan Xu Su Yao Zheng-He Xu Jin-Gang Liu Liang-Nian Ji 《Transition Metal Chemistry》2007,32(6):776-780
The effects of copper ion on the interaction of [Ru(bpy)2HPIP]2+(bpy = 2,2′-bipyridine, HPIP = 2-(2-hydroxyphenyl) imidazo [4,5-f] [1, 10] phenanthroline) with DNA have been investigated
by electronic absorption spectroscopy and fluorescence spectroscopy. HPIP ligand of the complex with an intramolecular hydrogen
bond can bind Cu2+ in the absence of DNA, as revealed by the absorbance and fluorescence decrease for [Ru(bpy)2HPIP]2+. The resultant heterometallic complex binds to DNA via intercalation of HPIP into the DNA base pairs and its DNA-binding ability is stronger than [Ru(bpy)2HPIP]2+ itself. The DNA bound [Ru(bpy)2HPIP]2+ cannot bind Cu2+ at low Cu2+ concentration and the intramolecular hydrogen bond in HPIP is located inside the DNA helix. While the Cu2+ concentration is relative high, Cu2+ can quench the fluorescence of DNA bound [Ru(bpy)2HPIP]2+. The quenching reason is proposed. 相似文献
123.
A simply fabricated microfluidic device using a green organic light emitting diode (OLED) and thin film interference filter as integrated excitation source is presented and applied to fluorescence detection of proteins. A layer-by-layer compact system consisting of glass/PDMS microchip, pinhole, excitation filter and OLED is designed and equipped with a coaxial optical fiber and for fluorescence detection a 300 microm thick excitation filter is employed for eliminating nearly 80% of the unwanted light emitted by OLEDs which has overlaped with the fluorescence spectrum of the dyes. The distance between OLED illuminant and microchannels is limited to approximately 1 mm for sensitive detection. The achieved fluorescence signal of 300 microM Rhodamine 6G is about 13 times as high as that without the excitation filter and 3.5 times the result of a perpendicular detection structure. This system has been used for fluorescence detection of Rhodamine 6G, Alexa 532 and BSA conjugates in 4% linear polyacrymide (LPA) buffer (in 1 x TBE, pH 8.3) and 1.4 fmol and 35 fmol mass detection limits at 0.7 nl injection volume for Alexa and Rhodamine dye have been obtained, respectively. 相似文献
124.
Hung‐Chuan Cheng Li‐Tang Wang Ashraf Taha Khalil Yao‐To Chang Yu‐Chi Lin Ya‐Ching Shen 《中国化学会会志》2004,51(2):431-435
Phytochemical investigation of the stem bark of Calophyllum inophyllum resulted in the isolation of a new dipyrenoxanthone, calophinone ( 1 ), together with four related xanthones ( 2–5 ). Identification of the isolated compounds was achieved through intensive studies of their spectral data, especially 2D NMR. 相似文献
125.
In order to achieve "postponement of school without suspension of learning" during the prevention and control of new coronavirus pneumonia, the online teaching strategy was constructed based on Enterprise WeChat and Integrated Online Education Platform for the online teaching of Separation Science and Technology. The student-centered teaching methods were applied in online teaching process. 相似文献
126.
Bao Liu Ling Huang Juntao Liu Yao Zhong Xingshu Li Albert S.C. Chan 《Tetrahedron: Asymmetry》2007,18(24):2901-2904
Chiral tridentate N-tosylated aminoimine ligands were used in the Cu(II)-catalyzed enantioselective addition of phenylacetylene to N-aryl arylimines, affording products up to 92% ee. 相似文献
127.
Chuan Zhou Tao Juan Li Xin Cui Yao Fu Qing Xiang Guo 《中国化学快报》2007,18(10):1199-1202
The possibility to carry out Cu-catalyzed cross-couplings under ligandless conditions was studied.It was found that by using K_3PO_4 as the base,the cross-coupling could proceed successfully between aryl iodides and several types of nucleophiles.Aryl bromides were completely inactive under the same reaction conditions. 相似文献
128.
129.
130.
J. Hatta M. Okada S. Matuoka H. Yao 《Journal of Thermal Analysis and Calorimetry》1992,38(8):1775-1783
Using an ac calorimetric method, detailed behaviour of the heat capacity in dipalmitoyl-phosphatidylcholine-cholesterol system was studied in the cholesterol concentration less than 5 mol%. It was revealed that the heat capacity near the main transition was composed of at least four anomalies, i.e., multipeak took place in the heat capacity. This fact indicates that a simple theory explaining coexistence of two phases in two component systems does not work in the multipeak region. Then, relation between the multipeak heat capacity and the change of the ripple structure with the cholesterol concentration should be taken into account, when we consider thermodynamical behaviour of the systems.
Zusammenfassung Mittels AC-Kalorimetrie wurde bei Cholesterol-Konzentrationen von weniger als 5 mol% das Verhalten der Wärmekapazität im System Dipalmitoylphosphatidylcholin-Cholesterol untersucht. Es wurde gezeigt, daß sich die Wärmekapazität in der Nähe der Hauptumwandlung aus mindestens vier Anomalien zusammensetzt, d.h. bei der Wärmekapazität kann ein Multipeak beobachtet werden. Diese Tatsache zeigt, daß eine einfache Theorie, welche die Koexistenz zweier Phasen in einem Zweikomponenten-System erklärt, für die Multipeakregion nicht geeignet ist. Weiterhin sollte bei Überlegungen zum thermodynamischen Verhalten von Systemen eine Beziehung zwischen der Multipeak-Wärmekapazität bzw. der Welligkeitsstruktur und der Cholesterol-Konzentration berücksichtigt werden.相似文献