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41.
42.
One-Pot Synthesis of Tetraarylpyrrolo[3, 2-b]pyrrole Dopant-Free Hole-Transport Materials for Inverted Perovskite Solar Cells 下载免费PDF全文
Liang-sheng Duan Quan-ping Wu Yuan-yuan Xu Hui Wang Zhe Sun Yu Chen Song Xue 《化学物理学报(中文版)》2021,34(2):217-226
Four organic small-molecule hole transport materials ( D41 , D42 , D43 and D44 ) of tetraarylpyrrolo[3, 2-b]pyrroles were prepared. They can be used without doping in the manufacture of the inverted planar perovskite solar cells. Tetraarylpyrrolo[3, 2-b]pyrroles are accessible for one-pot synthesis. D42 , D43 and D44 possess acceptor-\begin{document}$ \pi $\end{document} -donor-\begin{document}$ \pi $\end{document} -acceptor structure, on which the aryl bearing substitutes of cyan, fluorine and trifluoromethyl, respectively. Instead, the aryl moiety of D41 is in presence of methyl with a donor-\begin{document}$ \pi $\end{document} -donor-\begin{document}$ \pi $\end{document} -donor structure. The different substitutes significantly affected their molecular surface charge distribution and thin-film morphology, attributing to the electron-rich properties of fused pyrrole ring. The size of perovskite crystalline growth particles is affected by different molecular structures, and the electron-withdrawing cyan group of D42 is most conducive to the formation of large perovskite grains. The D42 fabricated devices with power conversion efficiency of 17.3% and retained 55% of the initial photoelectric conversion efficiency after 22 days in dark condition. The pyrrolo[3, 2-b]pyrrole is efficient electron-donating moiety for hole transporting materials to form good substrate in producing perovskite thin film.
相似文献
43.
将194例小肝癌患者纳入小肝癌组,185例肝细胞结节患者纳入结节组,所有患者均行MRI扩散加权成像(DWI-MRI),评估患者在DWI-MRI上的形态学表现及ADC值,检测患者血清AFP水平,比较不同检测方法诊断小肝癌的准确度、灵敏度、特异度。结果显示,应用DWI-MRI联合血清AFP诊断小肝癌的特异度、灵敏度和准确度均显著高于单独应用DWI-MRI,或血清AFP(P<0.05)。表明DWI-MRI联合血清AFP对小肝癌的诊断价值显著,可为病情评估提供切实可行的参考。 相似文献
44.
Eirini Chrysochou Panagiotis Georgios Kanellopoulos Konstantinos G. Koukoulakis Aikaterini Sakellari Sotirios Karavoltsos Minas Minaidis Evangelos Bakeas 《Molecules (Basel, Switzerland)》2021,26(11)
Cardiovascular diseases (CVDs) have been associated with environmental pollutants. The scope of this study is to assess any potential relation of polycyclic aromatic hydrocarbons (PAHs), their hydroxylated derivatives, and trace elements with heart failure via their direct determination in human serum of Greek citizens residing in different areas. Therefore, we analyzed 131 samples including cases (heart failure patients) and controls (healthy donors), and the respective demographic data were collected. Significantly higher concentrations (p < 0.05) were observed in cases’ serum regarding most of the examined PAHs and their derivatives with phenanthrene, fluorene, and fluoranthene being the most abundant (median of >50 μg L−1). Among the examined trace elements, As, Cd, Cu, Hg, Ni, and Pb were measured at statistically higher concentrations (p < 0.05) in cases’ samples, with only Cr being significantly higher in controls. The potential impact of environmental factors such as smoking and area of residence has been evaluated. Specific PAHs and trace elements could be possibly related with heart failure development. Atmospheric degradation and smoking habit appeared to have a significant impact on the analytes’ serum concentrations. PCA–logistic regression analysis could possibly reveal common mechanisms among the analytes enhancing the hypothesis that they may pose a significant risk for CVD development. 相似文献
45.
Theoretical insight of nitric oxide adsorption on neutral and charged Pdn (n = 1–5) clusters 下载免费PDF全文
Pakiza Begum Pranjal Gogoi Bhupesh Kumar Mishra Ramesh Chandra Deka 《International journal of quantum chemistry》2015,115(13):837-845
Density functional theory (DFT) calculations within the framework of generalized gradient approximation have been used to systematically investigate the adsorption of nitric oxide (NO) molecule on neutral, cationic, and anionic Pdn (n = 1–5) clusters. NO coordinate to one Pd atom of the cluster by the end‐on mode, where the tilted end‐on structure is more favorable due to the additional electron in the π* orbital. On the contrary, in the neutral and cationic Pd2 system, NO coordinates to the bridge site of cluster preferably by the side‐on mode. Charge transfer between Pd clusters and NO molecule and the corresponding weakening of N? O bond is an essential factor for the adsorption. The N? O stretching frequency follow the order of cationic > neutral > anionic. Binding energy of NO on anionic clusters is found to be greater than those of neutral and cationic clusters. © 2015 Wiley Periodicals, Inc. 相似文献
46.
Cooperative Lewis Pairs Based on Late Transition Metals: Activation of Small Molecules by Platinum(0) and B(C6F5)3 下载免费PDF全文
Sebastian J. K. Forrest Jamie Clifton Dr. Natalie Fey Prof. Paul G. Pringle Dr. Hazel A. Sparkes Prof. Duncan F. Wass 《Angewandte Chemie (International ed. in English)》2015,54(7):2223-2227
A Lewis basic platinum(0)–CO complex supported by a diphosphine ligand and B(C6F5)3 act cooperatively, in a manner reminiscent of a frustrated Lewis pair, to activate small molecules such as hydrogen, CO2, and ethene. This cooperative Lewis pair facilitates the coupling of CO and ethene in a new way. 相似文献
47.
Phase Behavior of a Designed Cyclopropyl Analogue of Monoolein: Implications for Low‐Temperature Membrane Protein Crystallization 下载免费PDF全文
Livia Salvati Manni Dr. Alexandru Zabara Dr. Yazmin M. Osornio Jendrik Schöppe Dr. Alexander Batyuk Prof. Dr. Andreas Plückthun Prof. Dr. Jay S. Siegel Prof. Dr. Raffaele Mezzenga Prof. Dr. Ehud M. Landau 《Angewandte Chemie (International ed. in English)》2015,54(3):1027-1031
Lipidic cubic phases (LCPs) are used in areas ranging from membrane biology to biodevices. Because some membrane proteins are notoriously unstable at room temperature, and available LCPs undergo transformation to lamellar phases at low temperatures, development of stable low‐temperature LCPs for biophysical studies of membrane proteins is called for. Monodihydrosterculin (MDS) is a designer lipid based on monoolein (MO) with a configurationally restricted cyclopropyl ring replacing the olefin. Small‐angle X‐ray scattering (SAXS) analyses revealed a phase diagram for MDS lacking the high‐temperature, highly curved reverse hexagonal phase typical for MO, and extending the cubic phase boundary to lower temperature, thereby establishing the relationship between lipid molecular structure and mesophase behavior. The use of MDS as a new material for LCP‐based membrane protein crystallization at low temperature was demonstrated by crystallizing bacteriorhodopsin at 20 °C as well as 4 °C. 相似文献
48.
Philipp M. Cromm Jochen Spiegel Dr. Tom N. Grossmann Prof. Dr. Herbert Waldmann 《Angewandte Chemie (International ed. in English)》2015,54(46):13516-13537
Small GTPases are a family of GDP‐/GTP‐binding proteins that serve as biomolecular switches inside cells to control a variety of essential cellular processes. Aberrant function and regulation of small GTPases is associated with a variety of human diseases, thus rendering these proteins highly interesting targets in drug discovery. However, this class of proteins has been considered “undruggable”, as intensive decade‐long efforts did not yield clinically relevant direct modulators of small GTPases. Recently, the targeting of small GTPases has gained fresh impetus through the discovery of novel transient cavities on the protein surfaces and the application of new targeting strategies. Besides Ras proteins, other small GTPases have attracted increased attention since improved biological insight in combination with novel targeting strategies identified them as promising targets in drug discovery. This Review gives an overview of relevant aspects of the superfamily of small GTPases and summarizes recent progress and perspectives for the direct modulation of these challenging targets. 相似文献
49.
Back Cover: CH Activation Generates Period‐Shortening Molecules That Target Cryptochrome in the Mammalian Circadian Clock (Angew. Chem. Int. Ed. 24/2015) 下载免费PDF全文
Tsuyoshi Oshima Dr. Iori Yamanaka Dr. Anupriya Kumar Dr. Junichiro Yamaguchi Dr. Taeko Nishiwaki‐Ohkawa Kei Muto Rika Kawamura Dr. Tsuyoshi Hirota Prof. Dr. Kazuhiro Yagita Prof. Dr. Stephan Irle Prof. Dr. Steve A. Kay Prof. Dr. Takashi Yoshimura Prof. Dr. Kenichiro Itami 《Angewandte Chemie (International ed. in English)》2015,54(24):7200-7200
50.
Dr. Colm Browne William J. Ramsay Dr. Tanya K. Ronson John Medley‐Hallam Prof. Jonathan R. Nitschke 《Angewandte Chemie (International ed. in English)》2015,54(38):11122-11127
The subcomponent self‐assembly of a bent dialdehyde ligand and different cationic and anionic templates led to the formation of two new metallosupramolecular architectures: a FeII4L6 molecular rectangle was isolated following reaction of the ligand with iron(II) tetrafluoroborate, and a M5L6 trigonal bipyramidal structure was constructed from either zinc(II) tetrafluoroborate or cadmium(II) trifluoromethanesulfonate. The spatially constrained arrangement of the three equatorial metal ions in the M5L6 structures was found to induce small‐molecule transformations. Atmospheric carbon dioxide was fixed as carbonate and bound to the equatorial metal centers in both the Zn5L6 and Cd5L6 assemblies, and sulfur dioxide was hydrated and bound as the sulfite dianion in the Zn5L6 structure. Subsequent in situ oxidation of the sulfite dianion resulted in a sulfate dianion bound within the supramolecular pocket. 相似文献