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71.
Masahiro Mizuno Atsushi Inagaki Makoto Yamashita Norie Soma Yoshiharu Maeda Hiroshi Nakatani 《Tetrahedron》2006,62(17):4065-4070
A practical method for the preparation of TAK-603, an antirheumatic drug, has been developed. As a result of optimizing the Friedel-Crafts reaction in the presence of SnCl4/POCl3, 2-aminobenzophenone skeleton, the key intermediate of TAK-603, was formed with good yield. The selective substitution reaction of 1,2,4-triazole was accomplished using 4-amino-1,2,4-triazole and deamination. 相似文献
72.
Nagatani H Suzuki S Fermín DJ Girault HH Nakatani K 《Analytical and bioanalytical chemistry》2006,386(3):633-638
The transfer mechanism of an amphoteric rhodamine, sulforhodamine 101 (SR101), across the polarized water/1,2-dichloroethane
(DCE) interface was investigated using cyclic voltammetry, differential voltfluorometry and potential-modulated fluorescence
(PMF) spectroscopy. The voltammetric response for the ion transfer of SR101 monoanion from water to DCE was observed as the
diffusion-controlled transfer process. An unusual voltammetric response was found at 0.15 V more negative than the formal
transfer potential of SR101−
in the cyclic voltammogram and voltfluorogram. The frequency dependence of the PMF responses confirmed the presence of the
adsorption processes at negative potentials. In addition, a further transient adsorption step was uncovered at The interfacial mechanism of SR101 is discussed by comparing the results obtained from each technique. 相似文献
73.
Susumu Takabayashi Keishi Okamoto Hiroaki Motoyama Tatsuyuki Nakatani Hiroyuki Sakaue Takayuki Takahagi 《Surface and interface analysis : SIA》2010,42(2):77-87
Oxygen‐related surface functional groups on diamond‐like carbon (DLC) films were derivatized with fluorine‐ and nitrogen‐related groups by the gas‐phase chemical derivatization (GCD) method, and the groups were analyzed quantitatively by X‐ray photoelectron spectroscopy (XPS). It is desirable that a derivatization reaction is unique to the target group; however, it usually causes undesirable side reactions which affect other groups. This diversity of the reactions has complicated the analysis. In this report, we have overcome the problem by applying a mathematical treatment which takes the side reactions into account. This improved analysis shows that it is no longer necessary to have derivatization reactions unique to the target groups. As a result, it is demonstrated that the carbonyl (C?O) group is the dominant surface functional group on both the DLC and its wet‐oxidized films, the carboxyl (COOH) group plays a minor role, and the presence of the hydroxyl (OH) group is logically denied. Considering the oxidation steps of these oxygen‐related surface functional groups, it is suggested that the C?O group on the DLC films requires the cleavage of the carbon–carbon bond with a relatively high activation energy barrier to change into the COOH group. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
74.
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76.
Viau L Bidault S Maury O Brasselet S Ledoux I Zyss J Ishow E Nakatani K Le Bozec H 《Journal of the American Chemical Society》2004,126(27):8386-8387
A new type of 4,4'-bis(styryl)-2,2'-bipyridine functionalized by a dialkylamino-azobenzene group has been prepared. This ligand has allowed the preparation of photoisomerizable octupolar tris(bipyridyl)zinc(II) complexes and the corresponding star-shaped polymer by atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA). The photoisomerization properties of such new metallo-chromophores have been studied. The macroscopic molecular orientation of the corresponding doped and grafted NLO-polymer films is reported for the first time. 相似文献
77.
Okino T Hoashi Y Furukawa T Xu X Takemoto Y 《Journal of the American Chemical Society》2005,127(1):119-125
We synthesized a new class of bifunctional catalysts bearing a thiourea moiety and an amino group on a chiral scaffold. Among them, thiourea 1e bearing 3,5-bis(trifluoromethyl)benzene and dimethylamino groups was revealed to be highly efficient for the asymmetric Michael reaction of 1,3-dicarbonyl compounds to nitroolefins. Furthermore, we have developed a new synthetic route for (R)-(-)-baclofen and a chiral quaternary carbon center with high enantioselectivity by Michael reaction. In these reactions, we assumed that a thiourea moiety and an amino group of the catalyst activates a nitroolefin and a 1,3-dicarbonyl compound, respectively, to afford the Michael adduct with high enantio- and diastereoselectivity. 相似文献
78.
The first Ritter-type reaction of alkylbenzenes with nitriles has been successfully achieved by the use of N-hydroxyphthalimide (NHPI) as a key catalyst. Thus, treatment of ethylbenzene with ammonium hexanitratocerate(IV) (CAN) in the presence of a catalytic amount of NHPI in EtCN under argon produced the corresponding amide in good selectivity. 相似文献
79.
Kobori A Horie S Suda H Saito I Nakatani K 《Journal of the American Chemical Society》2004,126(2):557-562
We have synthesized the first surface plasmon resonance (SPR) sensor that detects cytosine-cytosine (C[bond]C) mismatches in duplex DNA by immobilizing aminonaphthyridine dimer on the gold surface. The ligand consisting of two 2-aminonaphthyridine chromophores and an alkyl linker connecting them strongly stabilized the C[bond]C mismatches regardless of the flanking sequences. The fully matched duplexes were not stabilized at all under the same conditions. The C[bond]T, C[bond]A, and T[bond]T mismatches were also stabilized with a reduced efficiency. SPR analyses of mismatch-containing 27-mer duplexes were performed with the sensor surface on which the aminonaphthyridine dimer was immobilized. The response for the C[bond]C mismatch in 5'-GCC-3'/3'-CCG-5' was about 83 times stronger than that obtained for the fully matched duplex. The sensor successfully detects the C[bond]C mismatch at the concentration of 10 nM. SPR responses are proportional to the concentration of the C[bond]C mismatch in a range up to 200 nM. Aminonaphthyridine dimer could bind strongly to the C[bond]C mismatches having 10 possible flanking sequences with association constants in the order of 10(6) M(-1). The facile protonation of 2-aminonaphthyridine chromophore at pH 7 producing the hydrogen-bonding surface complementary to that of cytosine was most likely due to the remarkably high selectivity of 1 to the C[bond]C mismatch. 相似文献
80.
Enantioselective Michael reaction of malonates to nitroolefins catalyzed by bifunctional organocatalysts 总被引:1,自引:0,他引:1
Michael reaction of malonates to nitroolefins with chiral bifunctional organocatalysts, bearing both a thiourea and tertiary amino group, afforded Michael adducts with high yields and enantioselectivities (up to 95%, up to 93% ee). 相似文献