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541.
542.
Masahiro Sadakane Prof. Dr. Keiko Yamagata Katsunori Kodato Keisuke Endo Koshiro Toriumi Prof. Dr. Yoshiki Ozawa Prof. Dr. Tomoji Ozeki Prof. Dr. Takuro Nagai Dr. Yoshio Matsui Dr. Norihito Sakaguchi Prof. Dr. William D. Pyrz Douglas J. Buttrey Prof. Douglas A. Blom Dr. Thomas Vogt Dr. Wataru Ueda Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(21):3782-3786
Mix and match : The pentagonal [Mo6O21]n? polyoxomolybdate building block assembles with other sources of Mo, V, and Sb ions to form an orthorhombic Mo‐V‐Sb oxide. The first single‐crystal X‐ray analysis of an orthorhombic Mo–V‐based oxide, a promising catalyst for light alkane selective oxidation known as the “M1 phase”, revealed the structure of the compound.
543.
We report on the synthesis, stability, and photoluminescence (PL) properties of triphenylphosphine (PPh3)-stabilized PdAu10(PPh3)8Cl2 cluster, which is a mono-Pd-doped cluster of the well-studied Au11(PPh3)8Cl2 cluster. The PdAu10(PPh3)8Cl2 cluster was synthesized by simultaneously reducing two different metal complexes; AuCl(PPh3) and Pd(PPh3)4. Experimental evaluation of the stability showed that PdAu10(PPh3)8Cl2 is more stable against degradation in solution than the monometal Au11(PPh3)8Cl2 cluster. PL measurements revealed that PdAu10(PPh3)8Cl2 exhibits PL at 950?nm with a quantum yield of 1.5?×?10?3, which has not been observed for the monometal Au11(PPh3)8Cl2 cluster. The results indicate that Pd doping is a powerful method to produce clusters with higher stability and different physical properties than the monometal Au:PPh3 clusters. 相似文献
544.
Optically active silica nanoparticles, with a 70-nm diameter, grafted with (P)-1,12-dimethyl-8-methoxycarbonylbenzo[c]phenanthrene-5-carboxyamide were synthesized, and their use in the kinetic resolution of aromatic alcohols was examined. Up to 61% ee for (S)-2,2-dimethyl-1-phenyl-1-propanol was obtained by a preferential precipitation of aggregates formed with (P)-nanoparticles. 相似文献
545.
Kubo W Takahashi M Komoto A Okamoto K Miyata H 《Physical chemistry chemical physics : PCCP》2012,14(4):1418-1423
Exceptionally strong Bragg diffraction from a mesoporous silica film is achieved by exposing the as-deposited film to vapor of chlorotrimethylsilane (Me(3)SiCl) before extracting the surfactant. The intensity of the X-ray diffraction peak increased 7 times after the surfactant removal and it approached 30% reflectivity. This large increase of diffraction intensity cannot be explained simply by the improved contrast of the electron density, and rearrangement of the pore wall during the Me(3)SiCl vapor treatment is suggested. It is shown by infrared spectroscopy that Me(3)SiCl with a high grafting reactivity effectively caps the silanol groups and prevents the following condensation, which causes the structural degradation. The substitution of the hydrogen atom of hydroxyl groups with trimethylsilyl groups should help the improvement of the structural regularity by reducing the hydrogen bonds in the pore wall. The achieved strong diffraction opens the gate for the application of these regular mesoporous films prepared by a self-assembly process to optical elements in the X-ray region. 相似文献
546.
Devaraj NK Decreau RA Ebina W Collman JP Chidsey CE 《The journal of physical chemistry. B》2006,110(32):15955-15962
The rate of electron transfer is measured to two ferrocene and one iron tetraphenylporphyrin redox species coupled through terminal acetylenes to azide-terminated thiol monolayers by the Cu(I)-catalyzed azide-alkyne cycloaddition (a Sharpless "click" reaction) to form the 1,2,3-triazole linkage. The high yield, chemoselectivity, convenience, and broad applicability of this triazole formation reaction make such a modular assembly strategy very attractive. Electron-transfer rate constants from greater than 60,000 to 1 s(-1) are obtained by varying the length and conjugation of the electron-transfer bridge and by varying the surrounding diluent thiols in the monolayer. Triazole and the triazole carbonyl linkages provide similar electronic coupling for electron transfer as esters. The ability to vary the rate of electron transfer to many different redox species over many orders of magnitude by using modular coupling chemistry provides a convenient way to study and control the delivery of electrons to multielectron redox catalysts and similar interfacial systems that require controlled delivery of electrons. 相似文献
547.
Moriya M Tominaga S Hashimoto T Tanifuji K Matsumoto T Ohki Y Tatsumi K Kaneshiro J Uesu Y Sakamoto W Yogo T 《Inorganic chemistry》2012,51(8):4689-4693
A novel chiral coordination polymer, [Cu(C(6)H(5)CH(OH)COO)(μ-C(6)H(5)CH(OH)COO)] (1-L and 1-D), was synthesized through a reaction of copper acetate with L-mandelic acid at room temperature. Although previously reported copper mandelate prepared by hydrothermal reaction was a centrosymmetric coordination polymer because of the racemization of mandelic acid, the current coordination polymer shows noncentrosymmetry and a completely different structure from that previously reported. The X-ray crystallography for 1-L revealed that the copper center of the compound showed a highly distorted octahedral structure bridged by a chiral mandelate ligand in the unusual coordination mode to construct a one-dimensional (1D) zigzag chain structure. These 1D chains interdigitated each other to give a layered structure as a result of the formation of multiple aromatic interactions and hydrogen bonds between hydroxyl and carboxylate moieties at mandelate ligands. The coordination polymer 1-L belongs to the noncentrosymmetric space group of C2 to show piezoelectric properties and second harmonic generation (SHG) activity. 相似文献
548.
Let H be a real Hilbert space and let C be a nonempty closed convex subset of H. Let ?? >?0 and let A be an ??-inverse-strongly monotone mapping of C into H and let B be a maximal monotone operator on H. Let F be a maximal monotone operator on H such that the domain of F is included in C. Let 0?< k?<?1 and let g be a k-contraction of H into itself. Let V be a ${\overline{\gamma}}$ -strongly monotone and L-Lipschitzian continuous operator with ${\overline{\gamma} >0 }$ and L >?0. Take ${\mu, \gamma \in \mathbb R}$ as follows: $${0 < \mu < \frac{2\overline{\gamma}}{L^2}, \quad 0 < \gamma < \frac{\overline{\gamma}-\frac{L^2 \mu}{2}}{k}.}$$ In this paper, under the assumption ${(A+B)^{-1}0 \cap F^{-1}0 \neq \emptyset}$ , we prove a strong convergence theorem for finding a point ${z_0\in (A+B)^{-1}0\cap F^{-1}0}$ which is a unique solution of the hierarchical variational inequality $${\langle (V-\gamma g)z_0, q-z_0 \rangle \geq 0, \quad \forall q\in (A+B)^{-1}0 \cap F^{-1}0.}$$ Using this result, we obtain new and well-known strong convergence theorems in a Hilbert space which are useful in nonlinear analysis and optimization. 相似文献
549.
The synthesis of a dendron composed of tetrameric subphthalocyanine (SubPc) is accomplished by substituting the chlorine groups with phenoxy groups at the axial positions of SubPc with SubPc-triol. The present molecular design of the SubPc-triol introduces three phenol groups at the peripheral positions of the SubPc macrocycle as a tritopic template to construct SubPc dendrons. The self-polycondensation of SubPc-triol as a ‘divergent’ synthesis only gave a trace amount of the hyperbranched arrays due to poor solubility of the SubPc-triol. In contrast, a ‘convergent’ synthesis with the terminal SubPc improved the solubility throughout the reaction and a tetrameric SubPc dendron was obtained in moderate isolated yield. 相似文献
550.
Takashi Nagatomo Yoshio Kobayashi Michael K. Kubo Yasuhiro Yamada Mototsugu Mihara Wataru Sato Jun Miyazaki Kazuya Mae Shinji Sato Atsushi Kitagawa 《Hyperfine Interactions》2012,204(1-3):125-128
We measured the temperature dependence of 57Fe M?ssbauer spectra obtained after 57Mn implantation into polycrystalline LiH with an extremely low implantation dose. Density functional calculations suggested that the Fe atoms were predominantly implanted into both Li and H substitutional sites of the LiH crystal. 相似文献