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191.
Ge2Co6(CO)20: A Ge‐Co Cluster Compound from Solubilized GeBr The Ge‐Co cluster Ge2Co6(CO)20 is synthesized from a reaction of a GeBr solution with Co2(CO)8. Isolation of suitable crystals allows the determination of the crystal structure of Ge2Co6(CO)20, being the lacking member in the row GeCo4(CO)14 – Ge2Co6(CO)20 – Ge3Co8(CO)26. 相似文献
192.
Mina F. Shehata Melanie A. Short Matthew A. Sanders Jennifer L. Roizen 《Tetrahedron》2019,75(24):3186-3194
A general approach to prepare unsymmetrical sulfamides is described. This method relies on the activation of sulfamic acid salts with triphenylphosphine ditriflate, and subsequent trapping by a nucleophilic amine. This strategy improves access to N-octadecyl-N′-propylsulfamide, a feeding suppressant. 相似文献
193.
Dr. Daniela Hermann Dr. Heidi A. Schwartz Melanie Werker Prof. Dr. Dominik Schaniel Prof. Dr. Uwe Ruschewitz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(14):3606-3616
Fifteen new photochromic hybrid materials were synthesized by gas phase loading of fluorinated azobenzenes, namely ortho-tetrafluoroazobenzene (tF-AZB), 4H,4H′-octafluoroazobenzene (oF-AZB), and perfluoroazobenzene (pF-AZB), into the pores of the well-known metal-organic frameworks MOF-5, MIL-53(Al), MIL-53(Ga), MIL-68(Ga), and MIL-68(In). Their composition was analysed by elemental (CHNS) and DSC/TGA. For pF-AZB0.34@MIL-53(Al), a structural model based on high-resolution synchrotron powder diffraction data was developed and the host-guest and guest-guest interactions were elucidated from this model. These interactions of O−H⋅⋅⋅F and π⋅⋅⋅π type were confirmed by significant shifts of the O−H frequencies in loaded and unloaded MOFs of the MIL-53 and MIL-68 series. Most remarkably, all of the synthesized F-AZB@MOF systems can be switched with visible light, and some of them show almost quantitative (>95 %) photo-isomerization between its E and Z forms with no significant fatigue after repeated switching cycles. 相似文献
194.
Dr. María Mar Quesada-Moreno Dr. Pablo Pinacho Dr. Cristóbal Pérez Dr. Marina Šekutor Prof. Dr. Peter R. Schreiner Prof. Dr. Melanie Schnell 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(20):6198-6203
Fluorinated derivatives of biological molecules have proven to be highly efficient at modifying the biological activity of a given protein through changes in the stability and the kind of docking interactions. These interactions can be hindered or facilitated based on the hydrophilic/hydrophobic character of a particular protein region. Diadamantyl ether (C20H30O) possesses both kinds of docking sites, serving as a good template to model these important contacts with aromatic fluorinated counterparts. In this work, an experimental study on the structures of several complexes between diadamantyl ether and benzene as well as a series of fluorinated benzenes is reported to analyze the effect of H→F substitution on the interaction and structure of the resulting molecular clusters using rotational spectroscopy. All experimentally observed complexes are largely dominated by London dispersion interactions with the hydrogen-terminated surface areas of diadamantyl ether. Already single substitution of one hydrogen atom with fluorine changes the preferred docking site of the complexes. However, the overall contributions of the different intermolecular interactions are similar for the different complexes, contrary to previous studies focusing on the difference in interactions using fluorinated and non-fluorinated molecules. 相似文献
195.
The influence of topography on dynamic wetting 总被引:1,自引:0,他引:1
The paramount importance of wetting applications and the significant economic value of controlling wetting-based industrial processes has stimulated a deep interest in wetting science. In many industrial applications the motion of a complex liquid front over nano-textured surfaces controls the fate of the processes. However our knowledge of the impact of nano-heterogeneities on static and dynamic wetting is very limited. In this article, the fundamentals of wetting are briefly reviewed, with a particular focus on hysteresis and roughness issues. Present knowledge and models of dynamic wetting on smooth and rough surfaces are then examined, with particular attention devoted to the case of nano-topographical heterogeneities and solid–fluid–fluid systems. 相似文献
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197.
Patrick Fadden Kenneth H. Huang James M. Veal Paul M. Steed Amy F. Barabasz Briana Foley Mei Hu Jeffrey M. Partridge John Rice Anisa Scott Laura G. Dubois Tiffany A. Freed Melanie A. Rehder Silinski Thomas E. Barta Philip F. Hughes Andy Ommen Wei Ma Emilie D. Smith Angela Woodward Spangenberg Jeron Eaves Steven E. Hall 《Chemistry & biology》2010,17(7):686-694
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200.
Dukhan Kim Prof. Melanie S. Sanford Dr. Thomas P. Vaid Prof. Anne J. McNeil 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(25):e202200149
We describe the nonaqueous redox-matched flow battery (RMFB), where charge is stored on redox-active moieties covalently tethered to non-circulating, insoluble polymer beads and charge is transferred between the electrodes and the beads via soluble mediators with redox potentials matched to the active moieties on the beads. The RMFB reported herein uses ferrocene and viologen derivatives bound to crosslinked polystyrene beads. Charge storage in the beads leads to a high (approximately 1.0–1.7 M) effective concentration of active material in the reservoirs while preventing crossover of that material. The relatively low concentration of soluble mediators (15 mM) eliminates the need for high-solubility molecules to create high energy density batteries. Nernstian redox exchange between the beads and redox-matched mediators was fast relative to the cycle time of the RMFB. This approach is generalizable to many different redox-active moieties via attachment to the versatile Merrifield resin. 相似文献