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101.
In this study, we present the synthesis of 5-(3,5-dinitro-1H-pyrazol-4-yl)-1H-tetrazole and its energetic derivatives starting from 4-amino-3,5-dinitropyrazole, which was diazotized and cyanide substituted. A subsequent cycloaddition reaction with sodium azide led to 5-(3,5-dinitro-1H-pyrazol-4-yl)-1H-tetrazole ( 3 ). Several alkaline metal and nitrogen-rich salts were prepared and characterized by low-temperature X-ray diffraction. Additionally, all compounds were analyzed by vibrational spectroscopy (IR), 1H, 13C and 14N NMR spectroscopy, elemental analysis and differential thermal analysis (DTA). Additionally, the heats of formation for selected compounds were calculated using the atomization method based on CBS-4M enthalpies as well as important detonation parameters by using the EXPLO5 code (V6.05). Furthermore, the sensitivities of 3 and all synthesized salts toward friction, impact and electrostatic discharge according to BAM (Bundesamt für Materialforschung) were determined and compared to RDX. 相似文献
102.
Norbert Szimhardt Michael S. Gruhne Marcus Lommel Andreas Hess Maximilian H. H. Wurzenberger Thomas M. Klaptke Jrg Stierstorfer 《无机化学与普通化学杂志》2019,645(3):354-361
This contribution covers the preparation and characterization of 2,2‐bis(5‐tetrazolyl)propane (5‐DTP) ( 1 ). The bridged bitetrazole is used as a neutral nitrogen‐rich ligand in 3d transition metal(II) based complexes for the first time and can be synthesized via [2+3] cycloaddition from sodium azide and dimethylmalononitrile. The combination with different anions (e.g., perchlorate, nitrate, sulfate, and chloride) yields materials with widely varying physicochemical properties. The obtained coordination compounds were characterized using low‐temperature single‐crystal X‐ray diffraction (except 14 ), IR spectroscopy, elemental analysis, and DTA (except 16 ). The sensitivities toward external stimuli (impact and friction) were determined according to the Bundesamt für Materialforschung und ‐prüfung (BAM) standard methods together with its sensitivities against electrostatic discharge (except 16 ). Complexes 10 and 14 were characterized in laser ignition experiments. For determination of the compounds' deflagration to detonation transition (DDT) capability, hot plate and hot needle tests were performed for the zinc(II) and copper(II) perchlorate complexes. 相似文献
103.
Maximilian Diecke Claudio Schrenk Andreas Schnepf 《Angewandte Chemie (International ed. in English)》2020,59(34):14418-14422
The reduction of (nBu3P)AgCl with LiBH(sBu)3 in toluene gives the metalloid silver cluster Ag64(PnBu3)16Cl6 ( 1 ) as dark red, temperature‐ and light‐sensitive single crystals in high yield. 1 is the largest structurally characterized metalloid silver cluster exhibiting chlorine and phosphine substituents only. The silver atoms in 1 show an overall brick‐shape arrangement, where structural resemblance to the close‐packed fcc and hcp structures is realized. Within 1 a 58 electron closed shell system is present. The light sensitivity renders 1 as a model compound for the primary seeds of the photo process, whereby this sensitivity, together with the high‐yield synthesis show that 1 is a perfect starting compound for further investigations like silver‐plating processes. 相似文献
104.
E. Stroh 《Mathematische Annalen》1889,34(3):354-370
Ohne Zusammenfassung 相似文献
105.
E. Stroh 《Mathematische Annalen》1889,34(2):306-318
Ohne Zusammenfassung 相似文献
106.
E. Stroh 《Mathematische Annalen》1888,31(3):441-443
Ohne Zusammenfassung 相似文献
107.
Franz Maximilian Horn 《Fresenius' Journal of Analytical Chemistry》1888,27(1):163-165
Ohne ZusammenfassungAssistent an der K. K. technischen Hochschule in Wien. 相似文献
108.
Ferhat Can Özkaya Weaam Ebrahim Maximilian Klopotowski Zhen Liu 《Natural product research》2018,32(7):840-843
The anti-neuroinflammatory meroterpenoid citreohybridonol was isolated for the first time from a sponge-derived fungus Penicillium atrovenetum. In this study, in addition to isolation and structure featuring, its unambiguous absolute configuration was determined exclusively by single crystal X-ray diffraction. The C-17-keto tautomer was clearly observed in X-ray analysis. The substance crystallises in the monoclinic space group P21 with a = 10.7496(5) Å, b = 14.3286(7) Å, c = 17.4909(8) Å, β = 103.235(2)°, V = 2622.5(2) Å3, Z = 2, Dcalcd = 1.280 g/cm3. The chirality of the asymmetric carbon atoms was as follows: C3 (S), C5 (R), C6 (S), C8 (S), C9 (R), C10 (R), C13 (R), C14 (R). 相似文献
109.
Maximilian Von Strandtmann Marvin P. Cohen John Shavel 《Journal of heterocyclic chemistry》1970,7(6):1311-1319
The reaction of o-phenolic Mannich bases with enamines yields cyclic O,N-acetals having a 2-aminodihydropyran or a spiropyranopiperidine structure in common. The 2-aminodihydro-pyrans are easily converted to 2-hydroxydihydropyrans and to pyrans. The preparation of a large variety of pyran-containing fused ring systems is reported. 相似文献
110.
The fluorescence intensity from a planar multilayered system with a chromophore separated from a gold film by a dielectric spacer is measured quantitatively. The direction of excitation and the spacer thickness are varied and the angular distribution of the emission is recorded as well as its polarization. The experimental data are compared to the predictions obtained from classical electromagnetic theory, taking into account the refractive indices of the layer system as well as the nonradiative decay rate and the relative orientation of absorption and emission dipole moments of the dye. Excellent agreement is found for a spacer thickness above 15 nm if proper values for these parameters are used. Samples with thinner spacer layers show significant deviations from classical theory. 相似文献