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81.
Avramenko Andriy A. Shevchuk Igor V. Dmitrenko Nataliia P. Skitsko Ivan F. 《Journal of Thermal Analysis and Calorimetry》2022,147(22):12709-12719
Journal of Thermal Analysis and Calorimetry - The paper focuses on the analytical analysis of the propagation of a normal shock wave in an adiabatic gas flow with nanoparticles. A modified... 相似文献
82.
Perquinoline A–C: neuartige bakterielle Tetrahydroisochinoline mit einer bemerkenswerten Biosynthese
83.
84.
The synthesis of thiosemicarbazide of 1-butyl-6-fluoro-7-morpholino-4-oxo-1,4-dihydroquinoline-3-carboxylic acid as well as its heterocyclic derivatives – 1,3,4-thiadiazole and 1,2,4-triazole are described; the modification of proper 1,2,4-triazole derivative by maleimides is also presented. Spectral properties of the prepared compounds and X-ray analysis for the selected compounds were studied. For the compounds antitrypanosomal potential and the toxicity were determined. 相似文献
85.
Andriy Panasyuk 《Annals of Global Analysis and Geometry》1997,15(4):313-324
Given a complex manifold Mi, structures of Poisson algebras on (Mi)=C(Mi,C) which are associated with a nondegenerate -closed (2,0)-form i on Mi are considered. It is shown that every isomorphism of Poisson structures (M1) (M2) is generated by a biholomorphic map :M2 M1 such that 2 = *1 相似文献
86.
Moralez JG Raez J Yamazaki T Motkuri RK Kovalenko A Fenniri H 《Journal of the American Chemical Society》2005,127(23):8307-8309
The design of nanostructured materials with tunable dimensions and properties that maintain their structural integrity under physiological conditions is a major challenge in biomedical engineering and nanomedicine. Helical rosette nanotubes (HRN) are a new class of materials produced through a hierarchical self-assembly process of low molecular weight synthetic organic modules in water. Here, we describe a synthetic strategy to tune their stability and hierarchy by preorganization of the self-assembling units, control of net charge per unit of nanotube surface area, amphiphilicity, and number of H-bonds per self-assembling module, and through peripheral steric (de)compression. Using these criteria, HRNs with tunable stability and hierarchical architecture were produced from self-assembling modules that (a) persist as individual molecules in solution, (b) self-assemble into HRN but denature at high temperature (<85 degrees C), (c) self-assemble into HRN whose structural integrity persists even in boiling water (>95 degrees C), and (d) self-assemble into well-dispersed short nanotubes, long nanotubes, ribbons, or superhelices. Given the biocompatibility, synthetic accessibility, and chemical and physical tunability of these materials, numerous applications in biomedical engineering, materials science, and nanoscience and technology are envisioned. 相似文献
87.
Oleg Kasyan Elisabeth R. Healey Andriy Drapailo Mike Zaworotko Sebastien Cecillon Anthony W. Coleman Vitaly Kalchenko 《Journal of inclusion phenomena and macrocyclic chemistry》2007,58(1-2):127-132
The synthesis and X-ray structure investigation of the cone shaped monodecyloxythiacalix[4]arene, as well as the introduction of the reactive bromide or chloromethyl groups on it’s
upper rim are described. Preparation of the amphiphilic derivative of thiacalixarene bearing three hydrophilic diethoxyphosphoryl
groups at the upper rim and lipophilic decyloxy group at the lower rim is presented. 相似文献
88.
MSc. Andreas Meyer Prof. Dr. Andriy Mokhir 《Angewandte Chemie (International ed. in English)》2014,53(47):12840-12843
Known molecular, “caged” siRNAs are activated by UV light. Since the light of this type is toxic to cells, the uncaging can cause undesired side effects. A modular, molecular system for designing siRNAs is reported, which can be activated by non‐toxic light in live cells. For example, siRNAs responsive to green and red light are described. The uncaging is mediated by 1O2 photogenerated on a photosensitizer, which is attached to the 3′‐terminus of the lagging strand. The 5′‐terminus of the guide strand is alkylated (“caged”) with a 9‐anthracenyl residue. The latter fragment reacts with the 1O2 with formation of the free (uncaged) 5′‐OH terminus. Simultaneously with the uncaging the photosensitizer is bleached and no more 1O2 is generated after this process is completed. The photoactivation of the siRNAs described here is not toxic to cells. 相似文献
89.
Yakovenko Georgiy G. Lukianov Oleh А. Bol’but Andriy V. Vovk Mikhailo V. 《Chemistry of Heterocyclic Compounds》2019,55(12):1211-1216
Chemistry of Heterocyclic Compounds - N-Boc-protected 5-formyl-1H-pyrazol-4-amines react with malonic acid in pyridine in the presence of pyrrolidine at 45–50°С or with malonic... 相似文献
90.
David Smith Andriy Pysanenko Patrik Španěl 《Rapid communications in mass spectrometry : RCM》2010,24(7):1066-1074
A study has been carried out of the decay of ethanol in mouth‐exhaled and nose‐exhaled breath of two healthy volunteers following the ingestion of various doses of alcohol at different dilutions in water. Concurrent analyses of sequential single breath exhalations from the two volunteers were carried out using selected ion flow tube mass spectrometry, SIFT‐MS, on‐line and in real time continuously over some 200 min following each alcohol dose by simply switching sampling between the two volunteers. Thus, the time interval between breath exhalations was only a few minutes, and this results in well‐defined decay curves. Inspection of the mouth‐exhaled and nose‐exhaled breath data shows that mouth contamination of ethanol diminished to insignificant levels after a few minutes. The detailed results of the analyses of nose‐exhaled breath show that the peak levels and the decay rates of breath ethanol are dependent on the ethanol dose and the volume of ethanol/water mixture ingested. From these data, both the efficiency of the first‐pass metabolism of ethanol and the indications of gastric emptying rates at the various doses and ingested volumes have been obtained for the two volunteers. Additionally and simultaneously, acetaldehyde, acetic acid and acetone were measured in each single breath exhalation. Acetaldehyde, the primary product of ethanol metabolism, is seen to track the breath ethanol. Acetic acid, a possible secondary product of this metabolism, was detected in the exhaled breath, but was shown to largely originate in the oral cavity. Breath acetone was seen to increase over the long period of measurement due to the depletion of nutrients. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献