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131.
The phase diagrams of hexadecyl polyoxyethylene ether (C16POE10)/water/synthetic perfume, and sodium dodecyl sulfate (SDS)/water/synthetic perfume ternary systems were prepared. The synthetic perfumes used are, d-limonene, -hexylcinnamaldehyde, -ionone, benzyl acetate, linalool, and eugenol. In a series of C16POE10/water/synthetic perfume ternary systems, as the hydrophilicity of synthetic perfume increases, the regions of normal and inverse micellar solution phases were found to be extended, while that of the lamellar liquid crystal phase was reduced. Moreover, every region of normal micellar solutions, inverse micellar solutions, and lamellar liquid crystal phases in SDS/water/synthetic perfume ternary systems was found to be smaller than those in C16POE10/water/synthetic perfume systems. 相似文献
132.
133.
A general synthesis of 2?–5? linked oligoribonucleotides has been achieved on the basis of chemoselective formation of the 2?–5? internucleotide linkage using N-unblocked nucleosides. 相似文献
134.
Prof. Dr. Seiichi Uchiyama Kayo Yano Eiko Fukatsu Prof. Dr. A. Prasanna de Silva 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(36):8522-8527
One of the challenges for fluorescent sensors is to reduce their target environment size from a micrometer scale, such as biological cells, to a nanometer scale. Proton maps near membranes are of importance in bioenergetics and are the first goal in nanometer-scale analysis with fluorescent sensors. Thirty-three fluorescent photoinduced-electron-transfer pH sensors bearing an environment-sensitive benzofurazan fluorophore and having different hydrophobicity/hydrophilicity and hydrogen-bonding abilities were prepared. These sensors were scattered in nanospaces associated with anionic and cationic micelles as model membranes to indicate proton availability and polarity in local spaces. Gathering the data from the sensors allowed the successful drawing of proton maps near anionic and cationic micelles, in which electrostatic attraction/repulsion of protons by the charged head groups of micelles and dielectric suppression of protons were clearly observed. 相似文献
135.
136.
Construction of anomalously bent biphenyl structure using conformational properties of calix[4]amide
Masahide Tominaga Terutaka Hatano Masanobu Uchiyama Hyuma Masu Hiroyuki Kagechika Isao Azumaya 《Tetrahedron letters》2006,47(52):9369-9371
C2v-symmetrical cyclic tetramers of aromatic amides were simply synthesized in moderate yield by condensation reaction of N,N′-dimethyl-1,3-phenylenediamine and isophthalic acid derivatives using dichlorotriphenylphosphorane. The calix[4]amides exist in 1,3-alternate structure with cis conformation of tertiary aromatic amides, which were shown to be a versatile scaffold leading to a bowl-shaped macrocyclic compound possessing a anomalously strained structure, a bent hinge angle between two aromatic ring planes of biphenyl moiety, via an intramolecular ligation reaction. 相似文献
137.
Reductive Amination/Cyclization of Keto Acids Using a Hydrosilane for Selective Production of Lactams versus Cyclic Amines by Switching of the Indium Catalyst
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Dr. Yohei Ogiwara Takuya Uchiyama Prof. Dr. Norio Sakai 《Angewandte Chemie (International ed. in English)》2016,55(5):1864-1867
Described herein is that the catalytic construction of N‐substituted five‐ and six‐membered lactams from keto acids with primary amines by reductive amination, using an indium/silane combination. This relatively benign and safe catalyst/reductant system tolerates the use of a variety of functional groups, especially ones that are reduction‐sensitive. A direct switch from synthesizing lactams to synthesizing cyclic amines is achieved by changing the catalyst from In(OAc)3 to InI3. This conversion occurs by further reduction of the lactam using the indium/silane pair. 相似文献
138.
139.
Uchiyama M Furuyama T Kobayashi M Matsumoto Y Tanaka K 《Journal of the American Chemical Society》2006,128(26):8404-8405
A versatile preparation method for aromatic zincate compounds through a halogen-zinc exchange reaction using dilithium tetra-tert-butylzincate (tBu4ZnLi2) has been developed. This reagent permits efficient preparation of highly functionalized aromatic zincates, particularly, those with electrophilic functional groups, such as ester, amide, alcohol, and phenol. Halogen-zinc exchange reactions followed by electrophilic trapping (with allyl bromide or benzaldehyde) proved to be a powerful tool for C-C bond formation on functionalized aromatic rings. The functionalized aromatic zincate intermediate was also found to undergo copper- and palladium-catalyzed C-C bond-forming reactions with good yields and high chemoselectivity. 相似文献
140.
Uchiyama M Matsumoto Y Nobuto D Furuyama T Yamaguchi K Morokuma K 《Journal of the American Chemical Society》2006,128(27):8748-8750
The novel directed ortho metalation (DoM) reagents for functionalized aromatic rings, TMP-Zn-ates (R2Zn(TMP)Li (R = Me, 1; tBu, 2)), have been reported to be synthetically useful for the chemo- and regioselective construction of multi-functionalized aromatic compounds. Here, we present the first comprehensive structural and mechanistic investigation by means of X-ray, NMR, and DFT studies on the DoM reaction employing our original TMP-Zn-ate base. The structures of TMP-Zn-ates in solution and in the solid state were determined. The DFT study strongly suggested that the deprotonation involving the TMP ligand on the TMP-Zn-ate is kinetically more favorable than that involving the alkyl ligand, and this view was supported by monitoring of the 13C NMR spectrum of the reaction mixture. 相似文献