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81.
Circularly polarized luminescence (CPL) has attracted attention as a next-generation light signal because of its carrying more information compared with normal and linearly polarized lights as well as its potential wide application in information fields. Recently, much attention has been paid to small organic molecules-based CPL emitters because of easy synthesis, fine structural modification at molecular level, and tunable wide range emission wavelength. This review highlights the development of small organic molecules-based CPL emitters in the past 5 years (2017–2021). The progress suggests that small organic molecules-based CPL emitters provide a simple and efficient way to generate CPL. 相似文献
82.
Some short peptides can spontaneously self-assemble into various nanostructures via the synergistic driving forces of non-covalent interactions. These non-covalent interactions,including electrostatic interaction,hydrogen bonding,aromatic interactions and other non-covalent interactions,are usually highly coupled together. Through rational sequence design and proper modification of short peptide molecules,the driving forces could be regulated purposively,and the nanostructures and morphologies of the self-assemblies could be controlled accordingly,and thus so as to achieve the fabrication of peptide-based supramolecular biomaterials and develop their functions. In this paper,the effects of hydrogen bonding,π-π stacking, electrostatic interaction,hydrophobic interaction,metal ion coordination and chiral center on the self-assembly behavior of peptide self-assembly have been reviewed. The driving force regulation strategies, including sequence design,pH and concentration adjustment and metal ion coordination,and the resulted nanostructures have also been discussed. We also make the outlooks on the development of peptide-based supramolecular biomaterials with specific functions in biomedicines and biocatalysis. © 2022, Science Press (China). All rights reserved. 相似文献
83.
Validated multi‐drug determination using liquid chromatography with tandem mass spectrometry for the evaluation of a commercial drug disposal product 下载免费PDF全文
Veronica B. Waybright Stephanie H. Ma Kevin A. Schug 《Journal of separation science》2016,39(9):1666-1674
Currently, there are limited effective means of drug disposal for consumers, and this creates a gateway to illicit use and environmental contamination. Here, we evaluated the efficacy of a new drug disposal product, composed from a slurry of activated carbon, which claims to sequester up to 100% of a drug's active ingredient when the loading capacity is not exceeded, making it safe to dispose in landfill. High‐performance liquid chromatography with tandem mass spectrometry was applied to quantify as many as 24 drugs (opiates, barbiturates, statins, amphetamine, and benzodiazepine drugs) in the residual solvent solution from the product. Calibration curves were established in the concentration ranges of 0.25–7.0 μg/mL and showed good linearity. The limits of detection varied from 0.001 to 0.02 μg/mL, depending on the drug. Accuracy ranged from 80 to 111% for quality control samples, with a few minor exceptions. Precision overall varied between 0.2 to 12.7%. In sample bottles tested, where active ingredient of the loaded drug was below the maximum sorption capacity stated on the label, 98 to >99.9% of the active ingredient was sequestered. Percent active ingredient adsorbed was slightly lower in bottles loaded in excess of label specifications. 相似文献
84.
The binding of heterobidentate P∧S ligands introduces metal-centered chirality to the planar chiral parent complex Ru(η6:η1-NMe2C6H4C6H4PCy2)Cl2. Observed diastereomeric ratios for the kinetic product vary dramatically depending upon ring size of the chelate formed with the P∧S ligand. The complexes epimerize very slowly to thermodynamic product ratios that are substantially different from the kinetic product ratios. 相似文献
85.
Angelino Doppiu 《Journal of organometallic chemistry》2007,692(21):4495-4505
The optically active indenyl-linked phosphane ligands (S)-[2-(3H-inden-1-yl)-1-phenylethyl]diphenylphosphane (L1) and (S)-[2-(4,7-dimethyl-3H-inden-1-yl)-1-phenyl-ethyl]diphenylphosphane (L2) were synthesized in three steps from (R)-1-phenylethane-1,2-diol in excellent yields. Their lithium salts reacted with [Rh(μ-Cl)(η2-CH2CH2)2]2 at −78 °C in THF affording the planar chiral complexes (S,Rpl + Spl)-[Rh(η5-indenyl-CH2CH(Ph)PPh2-kP)(η2-CH2CH2)] and (S,Rpl + Spl)-[Rh(η5-4,7-dimethylindenyl-CH2CH(Ph)PPh2-kP)(η2-CH2CH2)] as 61:39 and 15:85 mixtures of diastereomers. The complexes were isolated in optically pure form by column chromatography. The stereochemical configuration of one of the diastereomers was determined by X-ray crystallography. The complexation of L2 was studied in different solvents and with several Rh precursors and diastereomeric excesses up to 76% were achieved. The ability of the chiral ligands to control the stereochemistry at the metal center was tested by oxidative addition of methyl iodide. Diastereomeric excesses greater than 98% were observed. 相似文献
86.
聚(酪氨酸酯对苯二甲酰胺)碳酸酯药物控制释放材料的研究 总被引:2,自引:0,他引:2
报道了一类生物可降解聚(酪氨酸酯对苯二甲酰胺)碳酸酯的合成和结构表征,研究了聚合物的性质和体外降解性能,并以5 氟脲嘧啶和牛血清白蛋为模型,对它们作为药物控制释放材料的性能进行了初步评价. 相似文献
87.
Alexandra Brown Victoria Hogan Jacob Perry Renuka Manchanayakage 《Tetrahedron letters》2017,58(11):1061-1065
Chiral ionic liquids show promising applications in various different fields. A series of pyrrolidinium-based chiral ionic liquids bearing a chiral cation, a chiral anion or both was prepared in good yields using an efficient, economic and simple pathway. The chirality was introduced using (l)-lactate and (l)-menthol derivatives. The resultant chiral compounds were characterized by both spectroscopy and polarimetry. We envision that these new chiral compounds can serve as effective reaction media and chiral catalysts for asymmetric reactions, which are presently being investigated in our lab. 相似文献
88.
89.
Both racemate and enantiomer of a novel double helix,binaphthylcyclooctaterthiophene(BN-COTh),which is a DNA-like molecule constructed by two single helices intertwined with each other via covalent bonds,have been synthesized with two building blocks,cycloocta-tetrathiophene(COTh) and cyclooctadinaphthyldithiophene(CONT) fused together via Negishi coupling reaction.Another homologue,dinaphthylcyclooctaterthiophene(DN-COTh) has been employed together as a model compound.Besides the synthetic work,BN-COTh and DN-COTh have been investigated by studying their crystal structures,spectroscopic behaviors,chiral resolution and chiral characteristics,including circular dichroism(CD) spectra and optical rotations.In addition,the novel crystal of enantiomer of(R,R,R)-BN-COTh has been explored.The enantiomer molecules packing along b-axis to form a larger and extended assembly packing due to intermolecular interactions between the enantiomer molecules and chloroform molecules in crystal. 相似文献
90.
A well-defined AB diblock copolymer of 2-vinyl-4,4-dimethylazlactone (VDA) and N,N-dimethylacrylamide (DMA) was generated by reversible addition-fragmentation chain transfer (RAFT) radical polymerization. The VDA-DMA diblock copolymer was reacted with 2-(methylthio)ethylamine (MTEA) and 3-(methylthio)propylamine (MTPA) to yield two novel thioether functional diblock copolymers whose structure was confirmed using 1H NMR and FTIR spectroscopy. Both diblock copolymers formed micelles (20–30 nm) in aqueous media as confirmed by dynamic light scattering (DLS) and transmission electron microscopy. The self-assembled micelles were loaded with Nile Red, a model hydrophobic drug to study their ROS-triggered release mechanism. On addition of hydrogen peroxide (H2O2), the most common ROS species, the hydrophobic thioether core of these micelles oxidized, and both diblock copolymers became more hydrophilic. This triggered their disassembly and subsequent cargo release as characterized by UV–visible spectroscopy. The Nile Red loaded micelles demonstrated similar in-vitro ROS-mediated release when exposed to endogenous oxidants in a model inflammation environment simulated by the presence of activated macrophages. The responsive nanomaterials developed in this article have promising potential as drug carriers in applications where ROS-triggered delivery of cargo is required such as in inflammatory conditions. 相似文献