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531.
Phthalazinone and pyridopyridazinone derivatives 3, 5, and 9 were prepared via reaction ofappropriate lactams 2 and 8 with 2-bromoethylphthalimide, N-tosylaziridine, and N,O-ditosyl derivatives of N-methylethanolamine in a two-step process in the presence of MeONa/MeOH or NaH/dimethylformamide (DMF). Starting compounds 2 and 8 were obtained by reaction of hydrazine hydrate with isoindolinones 1 or azaisoindolinones 6. Selected N-(2-phthalimidoethyl)-phthalazinones were converted into corresponding 2-[2-(methylamino) ethyl]- derivatives in satisfactory yields by treatment with hydrazine. 相似文献
532.
Karolina D?ugopolska Joanna Kisa?a Marek Danilczuk Dariusz Pogocki Tomasz Ruman 《Applied magnetic resonance》2010,38(3):321-335
In this paper, we present the detailed study on the correlation of the nuclear magnetic resonance (NMR) parameters with the results of density functional theory calculations performed for paramagnetic high-spin cobalt(II) complexes with trispyrazolylborate ligands. This work focuses on estimation of dipolar and contact shifts in mono-ligand high-spin cobalt(II) pyrazolylborate systems along with discussion on 1H NMR properties of the mentioned tetra-, penta- and hexacoordinate complexes. The calculation results show frontier molecular orbitals that may be responsible for contact shift. The calculated contact shift values are compared with the dipolar shift and hyperfine ones. 相似文献
533.
Dariusz Chruściński 《Journal of Russian Laser Research》2018,39(4):325-339
We provide conditions for the memory kernel governing the time-nonlocal quantum master equation which guarantee that the corresponding dynamical map is completely positive and trace-preserving. This approach gives rise to the new parametrization of dynamical maps in terms of two completely positive maps – so-called legitimate pair. In fact, these new parameterizations are a natural generalization of Markovian semigroup. Interestingly our class contains recently studied models like semi-Markov evolution and collision models. 相似文献
534.
Dariusz Dziki Urszula Gawlik-Dziki Wojciech Tarasiuk Renata Ryo 《Molecules (Basel, Switzerland)》2022,27(9)
This study aimed to investigate the possibility of utilizing oat by-products for fiber preparation. Oat husk (OH) and oat bran (OB) were micronized and used to prepare a novel product rich in fiber and with enhanced antioxidant properties. The basic chemical composition and phenolic acid profile were determined in OH and OB. The antioxidant properties of OH and OB were also analyzed. The type and strength of interactions between the biologically active compounds from their mixtures were characterized by an isobolographic analysis. The analyses showed that the sum of phenolic acids was higher in OH than in OB. Ferulic acid was dominant in both OH and OB; however, its content in OH was over sixfold higher than that in OB. The results also suggested that both OH and OB can be used for preparing fiber with enhanced antioxidant properties. The optimal composition of the preparation, with 60–70% of OH and 30–40% of OB, allows for obtaining a product with 60–70% fiber and enhanced antioxidant activity due to bioactive substances and their synergistic effect. The resulting product can be a valuable additive to various food and dietary supplements. 相似文献
535.
Dominik Straszak Agata Siwek Monika Guch-Lutwin Barbara Mordyl Marcin Koaczkowski Aldona Pietrzak Mansur Rahnama-Hezavah Bartomiej Drop Dariusz Matosiuk 《Molecules (Basel, Switzerland)》2022,27(9)
The μ-opioid receptors belong to the family of G protein-coupled receptors (GPCRs), and their activation triggers a cascade of intracellular relays with the final effect of analgesia. Classical agonists of this receptor, such as morphine, are the main targets in the treatment of both acute and chronic pain. However, the dangerous side effects, such as respiratory depression or addiction, significantly limit their widespread use. The allosteric centers of the receptors exhibit large structural diversity within particular types and even subtypes. Currently, a considerable interest is aroused by the modulation of μ-opioid receptors. The application of such a technique may result in a reduction in the dose or even discontinuation of classical opiates, thus eliminating the side effects typical of this class of drugs. Our aim is to obtain a series of 1-aryl-5,6(1H)dioxo-2,3-dihydroimidazo[1,2-a]imidazole derivatives and provide more information about their activity and selectivity on OP3 (MOP, human mu opioid receptor). The study was based on an observation that some carbonyl derivatives of 1-aryl-2-aminoimidazoline cooperate strongly with morphine or DAMGO in sub-threshold doses, producing similar results to those of normal active doses. To elucidate the possible mechanism of such enhancement, we performed a few in vitro functional tests (involving cAMP and β-arrestin recruitment) and a radioligand binding assay on CHO-K1 cells with the expression of the OP3 receptor. One of the compounds had no orthosteric affinity or intrinsic activity, but inhibited the efficiency of DAMGO. These results allow to conclude that this compound is a negative allosteric modulator (NAM) of the human μ-opioid receptor. 相似文献
536.
Ce2Ni2InHx hydrides with x < 2 retain the Mo2FeB2‐type structure of Ce2Ni2In and crystallize in the tetragonal space group P4/mbm (powder XRD). 相似文献
537.
The reactions of sodium dimethyl and diisopropyl phosphite, as well as dibenzylphosphinite with 4‐nitrobenzyl chloride, 9‐chlorofluorene, and diphenylchloromethane were studied in detail by the isolation and identification of all the products, and the examination of the effects of the solvents on the product distribution. The results of the performed experiments are compatible with the proposed mechanism: a >P‐O− anion acts toward an arylmethyl chloride as a base and abstracts a proton to form a carbanion, which can then participate in the SET processes to produce carbon‐centered radicals. Additionally, the >P‐O− reagent can act as a carbon‐centered radical trap if it is present in a high enough concentration. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 431–439, 1999 相似文献