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991.
Masato Mikami Kazuhiro Yamamoto Osamu Moriue Naoya Kojima 《Proceedings of the Combustion Institute》2005,30(2):2021-2028
Gas turbines, liquid rocket motors, and oil-fired furnaces utilize the spray combustion of continuously injected liquid fuels. In most cases, the liquid spray is mixed with an oxidizer prior to combustion, and further oxidizer is supplied from the outside of the spray to complete diffusion combustion. This rich premixed spray is called “partially premixed spray.” Partially premixed sprays have not been studied systematically although they are of practical importance. In the present study, the burning behavior of partially premixed sprays was experimentally studied with a newly developed spray burner. A fuel spray and an oxidizer, diluted with nitrogen, was injected into the air. The overall equivalence ratio of the spray jet was set larger than unity to establish partially premixed spray combustion. In the present burner, the mean droplet diameter of the atomized liquid fuel could be varied without varying the overall equivalence ratio of the spray jet. Two combustion modes with and without an internal flame were observed. As the mean droplet diameter was increased or the overall equivalence ratio of the spray jet was decreased, the transition from spray combustion only with an external group flame to that with the internal premixed flame occurred. The results suggest that the internal flame was supported by flammable mixture through the vaporization of fine droplets, and the passage of droplet clusters deformed the internal flame and caused internal flame oscillation. The existence of the internal premixed flame enhanced the vaporization of droplets in the post-premixed-flame zone within the external diffusion flame. 相似文献
992.
Shiro Matsuoka Yu Nakatsu K? Takehara Sulistyo Saputro Kazuhisa Yoshimura 《Analytical sciences》2006,22(12):1519-1524
A novel on-line oxidation method of ultra-trace Cr(III) dissolved in natural water has been developed using a flow electrolysis cell. This method was successfully applied to the determination of the total Cr concentration by flow injection-solid phase spectrophotometry using diphenylcarbazide as a coloring agent. With the applied potential of 1.35 V (vs. Ag/AgCl) and the flow rate of 0.80 cm(3) min(-1), Cr(III) was quantitatively oxidized to Cr(VI) at room temperature. The total Cr concentration of sub-microg dm(-3) in 3 - 4 samples could be determined within 1 h using an aqueous sample volume of 7.1 cm(3). The analytical values of the total Cr concentration in natural water were in good agreement with those obtained by ICP-MS. The detection limit of the proposed method was 0.014 microg dm(-3) (3sigma, n = 7). This method could be applied to the specific determination of Cr(III) and Cr(VI) in river water samples. 相似文献
993.
Yong He Jianchun Li Hiroshi Uyama Shiro Kobayashi Yoshio Inoue 《Journal of Polymer Science.Polymer Physics》2001,39(22):2898-2905
The intermolecular hydrogen‐bonding interaction and miscibility between enzymatically prepared novel polyphenols [poly(bisphenol A) and poly(p‐tert‐butyl phenol)] and poly(ε‐caprolactone) (PCL) were investigated as a function of composition by Fourier transform infrared spectroscopy (FTIR) and DSC. The blend films of PCL and polyphenols were prepared by casting polymer solution. The FTIR spectra clearly indicated that PCL and polyphenols interact through strong intermolecular hydrogen bonds formed between the PCL carbonyls and the polyphenol hydroxyl groups. The melting point and degree of crystallinity of the PCL component decreased with an increased polyphenol content. A single glass‐transition temperature was observed for the blend, and its value increased with the content of polyphenol, indicating that PCL and polyphenols are miscible in the amorphous state. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2898–2905, 2001 相似文献
994.
Long-term degradation tests regarding white light-emitting diodes based on InGaN were performed under accelerated current conditions, and the half-life of the light's output was estimated. An estimated mean half-life of 1.5×104 h was obtained under the recommended 20-mA operating condition. The change in the emission spectrum was found to be slight, and the color quality was considered generally satisfactory over the long term. 相似文献
995.
The spin flop behaviour of low anisotropy Mn ions within the mixed halide (54Mn)Mn(Br
x
Cl1−x
)2·4H2O is shown to be interpolative with that of the two terminal compounds, in striking contrast with the dynamics of nuclear
spin lattice relaxation. 相似文献
996.
Kenta Fujii Shiro Seki Koji Ohara Yasuo Kameda Hiroyuki Doi Soshi Saito Yasuhiro Umebayashi 《Journal of solution chemistry》2014,43(9-10):1655-1668
Ion-ion interactions or liquid structures in low-viscosity ionic liquid, 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)amide, [C2mIm+][FSA?] were investigated by high-energy X-ray diffraction (HEXRD) experiments and molecular dynamics (MD) simulations. Experimental X-ray structure factor, S exp(q) obtained from the HEXRD was successfully deconvoluted into the intra- and the intermolecular components, S intra exp (q) and S inter exp (q), respectively, by taking into account the population of cis and trans conformers of the FSA anion to give the corresponding radial distribution functions, G intra exp (r) and G inter exp (r), respectively. The G inter exp (r) exhibits the peaks at 3.5, 4.6 and 5.4 Å, which is well represented by theoretical radial distribution function, G inter MD (r) obtained from MD simulations. From the space distribution function, SDF calculated by MD simulations, it was found that static structure (distance and orientation) of the nearest neighbor intermolecular interaction between cation and anion in [C2mIm+][FSA?] is similar to its analogous ionic liquid, [C2mIm+][TFSA?] where TFSA is bis(trifluoromethanesulfonyl)amide. 相似文献
997.
Rycce S. Pratikha Takahiro Inoue Yuka Arai Tatsuhiro Kojima Nobuto Yoshinari Takumi Konno 《中国化学会会志》2020,67(12):2189-2197
The reaction of Na[CoIII(d -ebp)] (d -H4ebp = N,N′-ethylenebis[d -penicillamine]) with [(AuICl)2(dppe)] (dppe = 1,2-bis[diphenylphosphino]ethane) gave a cationic AuI4CoIII2 hexanuclear complex, [CoIII2(LAu4)]2+ ([ 1 ]2+), where [LAu4]4− is a cyclic tetragold(I) metalloligand with a 32-membered ring, [AuI4(dppe)2(d -ebp)2]4−. Complex [ 1 ]2+ crystallized with NO3− to produce a charge-separation (CS)-type ionic solid of [ 1 ](NO3)2. In [ 1 ](NO3)2, the complex cations are assembled to form cationic supramolecular hexamers of {[ 1 ]2+}6, which are closely packed in a face-centered cubic (fcc) lattice structure. The nitrate anions of [ 1 ](NO3)2 were accommodated in hydrophilic and hydrophobic tetrahedral interstices of the fcc structure to form tetrameric and hexameric nitrate clusters of {NO3−}4 and {NO3−}6, respectively. An analogous CS-type ionic solid formulated as [NiIICoIII(LAu4)](NO3) ([ 2 ](NO3)) was obtained when a 1:1 mixture of Na[CoIII(d -ebp)] and [NiII(d -H2ebp)] was reacted with [(AuICl)2(dppe)], accompanied by the conversion of the diamagnetic, square-planar [NiII(d -H2ebp)] to the paramagnetic, octahedral [NiII(d -ebp)]2−. While the overall fcc structure in [ 2 ](NO3) was similar to that of [ 1 ](NO3)2, none of the nitrate anions were accommodated in any hydrophobic tetrahedral interstice, reflecting the difference in the complex charges between [ 1 ]2+ and [ 2 ]+. 相似文献
998.
Dr. Sudhir Kumar Keshri Dr. Atsuro Takai Prof. Dr. Tomoya Ishizuka Prof. Dr. Takahiko Kojima Prof. Dr. Masayuki Takeuchi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(13):5292-5296
The design and synthesis of an enantiomeric pair of 1,8-diethynylanthracene-bridged naphthalenediimide (NDI)-based cyclophanes ( Cyclo-NDI s) are reported. Each enantiomer of Cyclo-NDI exhibits a circularly polarized luminescence signal with a relatively large luminescence dissymmetry factor (glum=±8×10−3). We have further investigated the modulation of through-space electronic communication between co-facially oriented NDIs in a discrete Cyclo-NDI with changes in the temperature. Tuning of the electronic communication results from the conformational transformation of monomer- versus dimer-like features of Cyclo-NDI , as confirmed by UV/Vis, fluorescence, circular dichroic, and NMR spectroscopic analysis. The temperature-dependent optical response in the Cyclo-NDI through the conformational transformation could be utilized as a highly sensitive and reversible optical thermometer in a wide temperature range (100 to −80 °C). 相似文献
999.
Inhibition of Heme Uptake in Pseudomonas aeruginosa by its Hemophore (HasAp) Bound to Synthetic Metal Complexes
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Chikako Shirataki Dr. Osami Shoji Mitsuyoshi Terada Prof. Dr. Shin‐ichi Ozaki Dr. Hiroshi Sugimoto Prof. Dr. Yoshitsugu Shiro Prof. Dr. Yoshihito Watanabe 《Angewandte Chemie (International ed. in English)》2014,53(11):2862-2866
The heme acquisition system A protein secreted by Pseudomonas aeruginosa (HasAp) can capture several synthetic metal complexes other than heme. The crystal structures of HasAp harboring synthetic metal complexes revealed only small perturbation of the overall HasAp structure. An inhibitory effect upon heme acquisition by HasAp bearing synthetic metal complexes was examined by monitoring the growth of Pseudomonas aeruginosa PAO1. HasAp bound to iron–phthalocyanine inhibits heme acquisition in the presence of heme‐bound HasAp as an iron source. 相似文献
1000.
Kinetic Resolution of Allyl Fluorides by Enantioselective Allylic Trifluoromethylation Based on Silicon‐Assisted CF Bond Cleavage
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