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831.
A long-range corrected (LC) time-dependent density functional theory (TDDFT) incorporating relativistic effects with spin-orbit couplings is presented. The relativistic effects are based on the two-component zeroth-order regular approximation Hamiltonian. Before calculating the electronic excitations, we calculated the ionization potentials (IPs) of alkaline metal, alkaline-earth metal, group 12 transition metal, and rare gas atoms as the minus orbital (spinor) energies on the basis of Koopmans' theorem. We found that both long-range exchange and spin-orbit coupling effects are required to obtain Koopmans' IPs, i.e., the orbital (spinor) energies, quantitatively in DFT calculations even for first-row transition metals and systems containing large short-range exchange effects. We then calculated the valence excitations of group 12 transition metal atoms and the Rydberg excitations of rare gas atoms using spin-orbit relativistic LC-TDDFT. We found that the long-range exchange and spin-orbit coupling effects significantly contribute to the electronic spectra of even light atoms if the atoms have low-lying excitations between orbital spinors of quite different electron distributions. 相似文献
832.
A review into the aza-Diels-Alder reaction, mainly concentrating on literature examples that form piperidin-4-ones from the reaction of imines and electron rich dienes or enones, either through a Lewis acidic/Br?nsted acid approach or through the use of an organocatalyst. This review questions whether the mechanism of the aza-Diels-Alder reaction is step wise as opposed to concerted when using oxygenated dienes. 相似文献
833.
Yasui T Omoto Y Osato K Kaji N Suzuki N Naito T Watanabe M Okamoto Y Tokeshi M Shamoto E Baba Y 《Lab on a chip》2011,11(19):3356-3360
We developed a new passive-type micromixer based on the baker's transformation and realized a fast mixing of a protein solution, which has lower diffusion constant. The baker's transformation is an ideal mixing method, but there is no report on the microfluidic baker's transformation (MBT), since it is required to fabricate the complicated three-dimensional (3D) structure to realize the MBT device. In this note, we successfully fabricate the MBT device by using precision diamond cutting of an oxygen-free copper substrate for the mould fabrication and PDMS replication. The MBT device with 10.4 mm mixing length enables us to achieve complete mixing of a FITC solution (D = 2.6 × 10(-10) m(2) s(-1)) within 51 ms and an IgG solution (D = 4.6 × 10(-11) m(2) s(-1)) within 306 ms. Its mixing speed is 70-fold higher for a FITC solution and 900-fold higher for an IgG solution than the mixing speed by the microchannel without MBT structures. The Péclet number to attain complete mixing in the MBT device is estimated to be 6.9 × 10(4). 相似文献
834.
Morikawa T Li X Nishida E Nakamura S Ninomiya K Matsuda H Hamao M Muraoka O Hayakawa T Yoshikawa M 《Chemical & pharmaceutical bulletin》2011,59(7):889-895
Five new triterpene saponins perennisosides VIII (1), IX (2), X (3), XI (4), and XII (5) were isolated from the MeOH-eluated fraction of the methanolic extract from the flowers of Bellis perennis. The MeOH-eluted fraction of the methanolic extract from the flowers of B. perennis was found to inhibit gastric emptying in olive oil-loaded mice at a dose of 200 mg/kg, per os (p.o.). The stereostructures of 1-5 were elucidated on the basis of chemical and spectroscopic evidence. 相似文献
835.
Horiuchi T Takeda Y Haginoya N Miyazaki M Nagata M Kitagawa M Akahane K Uoto K 《Chemical & pharmaceutical bulletin》2011,59(8):991-1002
The design, synthesis, and evaluation of novel thieno[2,3-d]pyrimidin-4-yl hydrazone analogues as cyclin-dependent kinase 4 (CDK4) inhibitors are described. In continuing our program aim to search for potent CDK4 inhibitors, the introduction of a thiazole group at the hydrazone part has led to marked enhancement of chemical stability. Furthermore, by focusing on the optimization at the C-4' position of the thiazole ring and the C-6 position of the thieno[2,3-d]pyrimidine moiety, compound 35 has been identified with efficacy in a xenograft model of HCT116 cells. In this paper, the potency, selectivity profile, and structure-activity relationships of our synthetic compounds are discussed. 相似文献
836.
Tanaka N Mizoshita N Maegawa Y Tani T Inagaki S Jorapur YR Shimada T 《Chemical communications (Cambridge, England)》2011,47(17):5025-5027
A novel spirobifluorene-bridged allylsilane precursor, which can be easily purified by silica gel chromatography, was prepared by using a new molecular building block for allylsilane sol-gel precursors (MBAS) and successfully converted into a highly fluorescent periodic mesoporous organosilica film. 相似文献
837.
Noguchi T Chikara C Kuroiwa K Kaneko K Kimizuka N 《Chemical communications (Cambridge, England)》2011,47(22):6455-6457
Supramolecular complexes consisting of anionic polyoxometalate (POM) and chiral, cationic lipids are newly developed. They give nanofibers, helical ribbons, and nanotapes in organic media depending on the chemical structure of lipid molecules. Lipid ammonium groups exert significant influence on their photoreduction characteristics. 相似文献
838.
Toru Takahashi Mayu Fukagawa Takao Sakurai Hitoshi Hoshino 《Journal of separation science》2020,43(3):657-662
The significant demands for single nucleotide polymorphism detection and genotyping assays have grown. Most common assays are based on the recognition of the target sequence by the hybridization with its specific probe having the complementary sequence of the target. Herein, a simple, label‐free, and economical non‐hybridization assay was developed for single nucleotide polymorphism detection and genotyping, based on the direct discrimination of single base mutation by simple capillary electrophoresis separation for single‐stranded DNA in an acidic electrophoretic buffer solution containing urea. Capillary electrophoresis separation of single‐base sequential isomers of DNA was achieved due to charge differences resulting from the different protonation properties of the DNA bases. Single nucleotide polymorphism detection and genotyping were achieved by discriminating the electropherogram pattern change, that is, peak number in the electropherogram, obtained by the proposed method. The successful practical application of the proposed method was demonstrated through single nucleotide polymorphism detection and genotyping on a known gene region of 84‐mer, in which guanine to adenine single‐base mutation is commonly observed, using a human hair sample in combination with genomic DNA extraction, polymerase chain reaction amplification, DNA purification from polymerase chain reaction products, and capillary electrophoresis separation. 相似文献
839.
Abstract Interfacial polycondensation in aqueous and non-aqueous systems has been investigated in order to synthesize various polyamides having functional groups. Rigid aromatic polyamides having pyridine moieties (PPy) were synthesized by interfacial polycondensation using an aqueous system and the solution properties of PPy in concentrated sulfuric acid were investigated in terms of solution viscosity and lyotropic behavior. Interfacial polycondensation in a non-aqueous system using two immiscible solvents was found to be useful for the synthesis of aromatic polyesters and copolyesters. 相似文献
840.
Norihiro Mizoshita Dr. Yasutomo Goto Dr. Mahendra P. Kapoor Dr. Toyoshi Shimada Prof. Dr. Takao Tani Dr. Shinji Inagaki Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(1):219-226
We report that 2,6‐naphthylene‐bridged periodic mesoporous organosilicas exhibit unique fluorescence behavior that reflects molecular‐scale periodicities in the framework. Periodic mesoporous organosilicas consisting of naphthalene–silica hybrid frameworks were synthesized by hydrolysis and condensation of a naphthalene‐derived organosilane precursor in the presence of a template surfactant. The morphologies and meso‐ and molecular‐scale periodicities of the organosilica materials strongly depend on the synthetic conditions. The naphthalene moieties embedded within the molecularly ordered framework exhibited a monomer‐band emission, whereas those embedded within the amorphous framework showed a broad emission attributed to an excimer band. These results suggest that the naphthalene moieties fixed within the crystal‐like framework are isolated in spite of their densely packed structure, different from conventional organosilica frameworks in which only excimer emission was observed for both the crystal‐like and amorphous frameworks at room temperature. This key finding suggests a potential to control interactions between organic groups and thus the optical properties of inorganic/organic hybrids. 相似文献